Disciple of Nagash said:
Sorry, one army I will be staying away from is marines, not my cup of tea..........
After Gunhearts I have a strange desire to get IG...
I'd reccomend Tau, playing them agressively is extremely fun, and often surprises your opponents. The normal Tau army is a gunline, in comparison, Mech Tau has alot of transports and quite a few battlesuits, anything which can't get the hell out of a given situation is useless (i.e Three basic squads with Devilfish, two Crisis squads, two hammerheads, Pathfinders with fish, a few Pirhannas, scouting Kroot are also good)>
In a way, similar to Wood Elves.
Dark Eldar also look interesting, I have an old article in a WD on how to play them well, and its frightening, after that they didn't look so much like the underdog, though the models are ancient. They also play quite like Woodelves, but with a bit of Khorne thrown in.
I'd advise either of those, just make sure to play agressively, they are much more fun than gunlines.