Hmmmmmmmm, A Grass or Electric Type is needed, I think, and, as you want special, yes, get rid of Snorlax. Here Are A Couple good Options, and I'll Narrow I Down.
Exeggutor: It Has The Highest Base Special Attack of all Grass Types, and Can Be An Exeggent(get it, oh, forget it, I mean excellent) Trick Roomer. With Powerful Attacks, It Can be a great pokemon.
Roserade: I Call This The Grass Version Of Milotic, as Its base stats are alot like milotics. Therefore, this would be giving you a powerful grass version of milotic.
Sceptile: Fits Your Style Perfect, Hit hard and Fast, plus its the balanced grass type you need.
Cacturne: Good Attack and Special Attack, and could be good with trick room, just as Exeggutor.
Magnezone: Its Strong, and Special, As You Want, with good movesets. It Has Good Defense too, for setting things up such as Magnet Rise.
Ampharos: Strong Special Attacker, with good Special Defense, too, plus good hp. Its Just What You Need
Jolteon/Manectric(they are basically the same): For Their Special Attacking Speed and Power, They Can Be Poweful pokemon, with pretty good movesets too:)
Narrowing it down:
Exeggutor: Basically just what you need
Roserade: A Replacement for Milotic
Magnezone: Powerful Electric Special Attacker, what you need
Ampharos: Another Powerful Sp. Attacker with Excellent movesets.
Finals: Roserade(Winner of The special grass types)
Magnezone(powerful with good steel combo)
Choose Who You Want But I Would Choose Roserade, as it basically means you get a stronger grass type Milotic:)