OK, I think I have my build for a mounted archer. I went with ranger, as I like the idea of having an animal companion double as a mount, and I get free proficiency in all martial weapons, thus forgoing the need to be an elf or take Martial Weapon Proficiency (longbow). Plus, I can still specialize in dungeoneering - picking aberrations or vermin as favored enemies, along with ranks in Knowledge (dungeoneering) will set my role in stone.
As for the choice of race - I like the idea of a group of adventurers being forced to accept a goblin mercenary, since they need a dungeon guide. There should be a good bit of "racial" tension.

There WILL be arguments when splitting the treasure - I'll see to it.
![Devious :] :]](http://www.enworld.org/forum/images/smilies/devious.png)
Well, here we are...
GOBLIN MERCENARY
Goblin, 1st-Level Ranger
Small Humanoid (Goblinoid)
Hit Dice: 1d8 (8 hp)
Initiative: +4
Speed: 30 ft. (6 squares)
Armor Class: 19 (+1 size, +4 Dex, +3 studded leather armor, +1 buckler), touch 15, flat-footed 15
Base Attack/Grapple: +1/-2
Attack: Scimitar +3 melee (1d4+1) or Kukri +3 melee (1d3+1) or Longbow +6 ranged (1d6)
Full Attack: Scimitar -1 melee (1d4+1) and Kukri -6 melee (1d3); or Longbow +6 ranged (1d6)
Space/Reach: 5 ft./5 ft.
Special Attacks: -
Special Qualities: Darkvision 60 ft., favored enemy (aberration), wild empathy
Saves: Fort +2, Ref +6, Will +2
Abilities: Str 12, Dex 18, Con 11, Int 10, Wis 14, Cha 6
Skills: Hide +8, Knowledge (dungeoneering) +4, Knowledge (nature) +2, Listen +2, Move Silently +8, Search +2, Spot +2, Survival +4
Feats: Point Blank Shot, Track
Alignment: Neutral
Equipment: Small explorer's outfit, small suit of studded leather armor, small buckler, small scimitar, small kukri, small longbow, 40 small arrows w/ small quiver, small backpack, small sack, small waterskin, small bedroll, flint and steel, whetstone, 3 torches, 1 day's small trail rations
Coins: 5 gold pieces, 2 silver pieces, 5 copper pieces
Spells: None
Languages: Common, Goblin
Naturally, I'm going to select Archery for my Combat Style. I won't take Weapon Finesse, since I'm not a melee fighter - I'm an archer. I can use that feat space much more effectively with an archery feat. For melee, a scimitar (and later a falchion) will get the job done fine. When I can afford it, I'll grab a Composite Longbow (+1 Str). I might even get a Mithral Breastplate!
The buckler is there mostly for the scimitar, but I might ditch it eventually. I can get rid of the armor check penalty by getting a masterwork, but I don't know about that -1 to attack rolls for melee weapons... it loses its shield bonus when you use a weapon in your off hand, meaning that it will only hinder the falchion... but does it lose the shield bonus when used with a longbow? If it doesn't, I'll DEFINITELY keep it, for a little extra protection from ranged attacks.
Now, for feats... I plan to be equally good as a long-range sniper and a close-range arrow-loosing powerhouse, all from the back of a mount. Therefore, I do plan on taking Point Blank Shot and Far Shot. Dungeons can be full of wide, open spaces, or they might have tons of tight, twisty corridors - underground areas are my specialty, I plan to be able to function in ANY situation. Granted, I won't be as good at long-range sniping as a dedicated long-range archer, and I won't have the pure staying power of a specialized close-range archer, but I'll make up for it with ingenuity and versatility.
On the subject of Rapid Shot and Manyshot - can I stack them? Rapid Shot has to be full-round, and Manyshot can be a standard action, but can I use Manyshot with a full-round action, combining it with Rapid Shot for a hail of arrows? And when I get multiple attacks from my base attack bonus, can I use Manyshot multiple times in a full-round action, possibly in conjunction with Rapid Shot (to literally DARKEN the sky with arrows)?
At level 3, I'm going to start putting ranks into Ride and Handle Animal, along with taking Mounted Combat, in preparation for getting a wolf animal companion / mount. At level 8, I'm switching to a Worg animal companion, and I'll take various Mounted Archery and Ranged Combat feats along the way.
And finally... any suggestions for improvement or change?