Hm... well if you are looking for a tank, I would recommend Magnazone with Iron Defense, Lock-On, Zap Cannon, and the last move would be up to you. If your looking for a raptor (fast Pokemon) I would recommend either Jolteon or something. But if your looking for a status giver, I highly recommend Togekiss with the ParaFlinch moveset, which is Air Slash, Thunder Wave, and the last two moves are also up to you. Also, make sure the Togekiss has the Serene Grace ability, which boosts the likelihood of added effects, such as flinching. But I don't understand why you'd want to get rid of Snorlax, it's a great tank, and it can be a great status pro if you give it the right moveset. Of course, the choice is up to you. But if it were up to me, I wouldn't replace Snorlax. I'd probably replace Garchomp with Dragonite, since Dragonite is faster, more tanky, and can take alot of damage if it has the Multiscale ability. And the fact that you can teach Dragonite a lot of different moves to help with some of it's disadvantages, like say your facing an Aerodactyl, which is faster than both Garchomp and Dragonite. If you have the multiscale ability, Dragonite can take the first Rock Slide or Smack Down and then strike back with Waterfall or Thunder. But still the choice is all yours.
