Okay, here are some ranged suggestion from MP. Pick and choose at your discretion.
Encounter powers
Level 1
In place of the melee only Positioning strike
Impact Shot
Your shot slams your foe backward.
Encounter Martial, Weapon
Standard Action Ranged weapon
Requirement: You must be wielding a crossbow, a light thrown weapon, or a sling.
Target: One creature
Attack: Dexterity vs. AC
Hit: 2[W] + Dexterity modifier damage, and you push the target 1 square.
Or
Unbalancing Shot
The impact of your shot leaves your enemy wobbly.
Encounter Martial, Weapon
Standard Action Ranged weapon
Requirement: You must be wielding a crossbow, a light thrown weapon, or a sling.
Target: One creature
Attack: Dexterity vs. AC
Hit: 2[W] + Dexterity modifier damage, and the target is slowed until the end of your next turn
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Level 3
In place of the melee only Bait and Switch
Trickster's Blade
You land an expert blow and follow up with a clever series of feints that bewilder your enemies.
Encounter Martial, Weapon
Standard Action Melee or Ranged weapon
Requirement: You must be wielding a crossbow, a light blade, or a sling.
Target: One creature
Attack: Dexterity vs. AC
Hit: 2[W] + Dexterity modifier damage. Add your Charisma modifier to your AC until the start of your next turn
This one is actually from the PHB and is melee or ranged and uses your charisma to good effect. Maybe you missed it. It's a good option if you get cornered (get the extra AC) and if this doesn't happen you can still unload it at range for the extra damage.
Otherwise, even MP doesn't offer good ranged options unless you are a Ruthless Ruffian.
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Level 7
Cloud of steel is pretty good though as I said it is used squarely in melee.
But look at that Artful dodger firendly encounter power ;
From the Shadows
You spring from the shadows to strike, and then you fade away as if you were never there.
Encounter Martial, Weapon
Standard Action Melee or Ranged weapon
Requirement: You must be wielding a crossbow, a light blade, or a sling.
Target: One creature
Effect: Before the attack, you can shift 2 squares. If the target could not see you before the shift, you gain combat advantage for this attack.
Attack: Dexterity vs. AC
Hit: 1[W] + Dexterity modifier damage, and you can shift 2 squares. If you have any cover or concealment after this shift, you can make a Stealth check as a free action.
Artful Dodger: Before the attack and after the hit, you can instead shift a number of squares equal to 1 + your Charisma modifier.
Can I hear a 'Wow!' ? This power means that if you start out of sight, even if you are not successfully hidden by a stealth check, you can still get your sneak attack and then move back to safety and make immediately a new check even if you only have cover or concealment (As opposed to needing no LOS, superior cover or superiuor concelament in normal circumstances).
And with your high charisma, you cover a lot of ground! Shift 6 square before and six square after! And it's actually melee or ranged.
Its only competition would be this power from the PHB that you might have missed
Rogue's Luck
A gifted rogue can turn failure into fortune.
Encounter Martial, Weapon
Standard Action Melee or Ranged weapon
Requirement: You must be wielding a crossbow, a light blade, or a sling.
Target: One creature
Attack: Dexterity vs. AC
Hit: 2[W] + Dexterity modifier damage.
Miss: Make a secondary attack against the target.
Secondary Attack: Dexterity vs. AC
Artful Dodger: You gain a bonus to the attack roll for the secondary attack equal to your Charisma modifier.
Hit: 1[W] + Dexterity modifier damage.
This power is a little unassuming but it's a 'I need this sneak attack to land RIGHT NOW!' kind of power. If you are trying to kill a dragon before he breaths again or something of the sort, it's worthwhile. Still, it's a little specialized and Cloud of steel bears the comparison well.
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Daily
Blinding barrage is pretty good because, well, it blinds. Especially with 2 rogues on the team... If you want to keep some blast power, this ain't half a bad choice.
For consideration, here is IMO the main contender as a ranged Daily for that level.
Confounding Attack
Your attack causes your opponent to accidentally wallop his ally.
Daily Martial, Weapon
Standard Action Melee or Ranged weapon
Requirement: You must be wielding a crossbow, a light blade, or a sling.
Target: One creature
Attack: Dexterity vs. AC
Hit: 2[W] + Dexterity modifier damage.
Effect: As a free action, the target makes a melee basic attack against a creature of your choice adjacent to it. If you or the target has combat advantage against the creature and you haven’t dealt your Sneak Attack damage during this round, you can deal your Sneak Attack damage against the creature.
Level 5
Walking Wounded actually is a ranged power. In the right circumstances, it is devastating (Against a tough and mobile elite or solo, you have just single handedly shut down the fight). It's so-so in other circumstances but still a good power to have on the book.
Other options
Compel the Craven
Your unnerving attack forces your foe to run away from you, heedless of its enemies.
Daily Fear, Martial, Rattling, Weapon
Standard Action Melee or Ranged weapon
Requirement: You must be wielding a crossbow, a light blade, or a sling.
Target: One creature
Attack: Dexterity vs. Will
Hit: 2[W] + Dexterity modifier damage, and the target moves away from you a number of squares equal to your Charisma modifier, avoiding unsafe squares and difficult terrain if it can.
Miss: The target moves 1 square away from you, avoiding unsafe squares and difficult terrain if it can
The amusing thing here is that the power causes the enemy to move away. Not slide or whatever. So it provokes Opportunity attack! Dagran, Nathan and Kern all have decents OA. Note that it is a fear effect, something to consider before using it on someone who might be immune.
Another one worth consideration
Staggering Assault
You deal a savage strike that staggers your adversary.
Daily Martial, Weapon
Standard Action Melee or Ranged weapon
Requirement: You must be wielding a crossbow, a light blade, or a sling.
Target: One creature
Attack: Dexterity vs. AC
Hit: 2[W] + Dexterity modifier damage, and the target is slowed (save ends). If the target is not bloodied when you make this attack, the attack deals 1[W] extra damage.
Effect: Until the end of the encounter, when you hit the target, it is slowed (save ends).
It's basically a less extreme version of walking wounded but you are guaranteed a chance to slow him for most of the fight (See Effect line) instead of being all or nothing. Plus, it does a bit more damage on a fresh enemy.
Level 9
Knock out is cool, main flaw being again that it is melee only.
Agonizing Shot
Your precise aim finds a weak spot.
Daily Martial, Weapon
Standard Action Ranged weapon
Requirement: You must be wielding a crossbow, a light thrown weapon, or a sling.
Target: One creature
Attack: Dexterity vs. Reflex
Hit: 1[W] + Dexterity modifier damage, and the target is slowed and takes ongoing 10 damage (save ends both).
Aftereffect: The target is slowed and takes ongoing 5 damage (save ends both).
Miss: Half damage, no ongoing damage, and the target is slowed (save ends).
Pretty good all around for a variety of reasons; it targets reflex so it hits more than vs AC, it guarantees at least a slow effect plus the ongoing damage is even better than it looks because Kern is a Death Dealer and inflicts a -2 to save to enemy adjacent to him.
Burst Fire
You loose missiles in an unpredictable pattern.
Daily Martial, Weapon
Standard Action Area burst 1 within 10 squares
Requirement: You must be wielding a crossbow, a light thrown weapon, or a sling.
Target: Each enemy in burst you can see
Attack: Dexterity vs. Reflex
Hit: 2[W] + Dexterity modifier damage.
Miss: Half damage.
Actually a rogue ranged area attack. Mostly noteworthy for that reason.
Rogue's Recovery
With a cunning attack, you create a new opportunity for yourself.
Daily Martial, Weapon
Standard Action Melee or Ranged weapon
Requirement: You must be wielding a crossbow, a light blade, or a sling.
Target: One creature
Attack: Dexterity vs. AC
Hit: 2[W] + Dexterity modifier damage.
Effect: If you have used all your encounter attack powers, you regain the use of a rogue encounter attack power you have used during this encounter. Or if you have combat advantage against the target, you can instead deal 2[W] extra damage with the attack.
Recovering an encounter power of your choice is neat in a long fight.
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There you go. So more options.