Lemme nit-pick a bit:
Role - Yeah, I don't really see how this is a controller. I see a funny striker that is well armed, a little defenderish and that happens to get small area attacks. Neat, but not a controller in the least.
Key AbilitiesYou sure you want int? Kind of an odd fit for most of the powers fluff, and wisdom is supposed to be the polearm stat anyways.
Weapon Proficiencies - I see you gave them no ranged weapons, but ranged powers, thereby limiting them to thrown weapons. That's handy and all, but you should really put the intended weapon in the power requirements.
Roundabout Capability - No complaints, just want to say that's a cool defender-lite ability
Lancer Tactics - Just give them full stat bonuses, I don't think half-stats apply anywhere in 4e. It's right in line with other classes features anyway.
Spinning Strike - you meant a close burst, right? Regular bursts happen at range, and this doesn't sound like that at all. And it suddenly gets a str mod at level 21, which it shouldn't (and it's a bit too good then besides)
Piercing Thrust - I would really expect this (and some other powers) to use dex instead of int. This sounds like it should be polearm only. It also sounds like stabbing through one guy and poking the guy behind him... the fluff and mechanics don't match the name.
Burst Strike - Again with the stat bonus at epic.
Defensive Spin - instead of the power bonuses, it may be simpler to apply an additional stat to ac and reflex. I say Str works fine for this, or Wis if you went with implementing that stat.
Vertical Shot - Make this for Light or Heavy throwing weapons only, and state which uses what stat.
Encounter and Daily powers - Nothing in particular really catches my eye right now, but keywords are wonky and the half-stats need to go.
Also, NEEDS MORE JUMPING.
Role - Yeah, I don't really see how this is a controller. I see a funny striker that is well armed, a little defenderish and that happens to get small area attacks. Neat, but not a controller in the least.
Key AbilitiesYou sure you want int? Kind of an odd fit for most of the powers fluff, and wisdom is supposed to be the polearm stat anyways.
Weapon Proficiencies - I see you gave them no ranged weapons, but ranged powers, thereby limiting them to thrown weapons. That's handy and all, but you should really put the intended weapon in the power requirements.
Roundabout Capability - No complaints, just want to say that's a cool defender-lite ability

Lancer Tactics - Just give them full stat bonuses, I don't think half-stats apply anywhere in 4e. It's right in line with other classes features anyway.
Spinning Strike - you meant a close burst, right? Regular bursts happen at range, and this doesn't sound like that at all. And it suddenly gets a str mod at level 21, which it shouldn't (and it's a bit too good then besides)
Piercing Thrust - I would really expect this (and some other powers) to use dex instead of int. This sounds like it should be polearm only. It also sounds like stabbing through one guy and poking the guy behind him... the fluff and mechanics don't match the name.
Burst Strike - Again with the stat bonus at epic.
Defensive Spin - instead of the power bonuses, it may be simpler to apply an additional stat to ac and reflex. I say Str works fine for this, or Wis if you went with implementing that stat.
Vertical Shot - Make this for Light or Heavy throwing weapons only, and state which uses what stat.
Encounter and Daily powers - Nothing in particular really catches my eye right now, but keywords are wonky and the half-stats need to go.
Also, NEEDS MORE JUMPING.