Instead of Lone Wolf, a Glass Cannon archer with guerilla is pretty amazing in a full party.
Huntsman is great, keep putting points for height damage bonus, there is a skill to escape a bad situation in there,
Scoundrel for movement in battle and dodging (I *think* thats a passive for scoundrel - I quit awhile ago, waiting for the bugginess of it all to get fixed), plus there are a couple skills in there that will work good for an archer - just don't waste too many points in it.
Polymorph for the flying skill (saved me a few times, plus it's great for relocating once your position has been compromised. And the extra points for attributes are nice. Again, you don't need too many in polymorph.
Aerothurge - ALL characters should have the Teleportation skill. Incredibly useful for non-melee characters when the enemy is approaching your position, and melee's to help those same characters while theirs is cooling down. I believe its 2 points for the skill - if not a mage, no character should get more than that.
Necromancer - 1 point for Blood Sucker. Your mage can get 2 for Blood Rain, the other party members all with blood sucker will heal from it.
Attributes: (In order) - Finesse, Wits, Memory. Wits is VERY important for every build - it's like the Speed attribute from the 1st game. It increases critical chance, but even more important it determines your initiative. You are going to want your party to act before the enemy as much as possible.
So basically, you want to look at the skills for each school and see what would work well with your archer - or any non-mage (Polymorph's Tentacle Lash is amazing for Fighters since it scales with STR), non-intel based ones except for things like teleport. Then only spend enough points to get those skills. The rest into Huntsman and Ranged.
With Guerilla, I would separate my archer from the party before a battle and sneak him into the best spot I can without accidentally getting spotted, preferably at a high point but many times an enemy is up there so I'd just get as close to the ladder as possible, then rush my team in to start battle, go back to my archer and have him go up the stairs since that enemy is now looking the other way. A guerilla shot from height advantage first for big damage, teleport the enemy archer or mage off your platform to the ground, and you still have one more shot with glass cannon.
He was my biggest damage dealer second to my rogue (also glass cannon). My fighter was a major tank and I always tried to use Provoke to keep enemies on him, unfortunately the range on that is ridiculously small - if enemies are THAT close to you already, they already ARE attacking you - the range of that made no sense to me.
Oh yeah, almost forgot, also use the talent Stench on a guerilla, glass cannon archer so the enemies go after him much less.
Forgot another thing - I *think* its in Polymorph (might be a scoundrel skill though), but get 2 other skills - 1 makes you invisible without breaking sneaking (use it first, then sneak in those occasions sneaking is impossible in battle) and the other teleports you without breaking sneaking. Both are great for a rogue as well.
*FULL DISCLOSURE: I 'slightly' cheat - I use a mod that makes sneaking in battle cost 2ap instead of 4 ... this makes glass cannon even better as you still have 2 attacks. Costing 4ap wouldn't be worth it - better to just get off 3 shots from high ground.
Anyway thats how I played mine, and he was pretty, pretty, pretty good.