I decided to rate your team!
Synergy/Typing
The typing in your team seems to be good. You have a 2x Weakness to Rock and a 4x weakness to Water, but that's all. You also have a decent amount of resistances, which is good.
You could have a good spinner / defogger on your team (such as Warturtle / Togetic), but that depends if you're having trouble with entry hazards.
I'm not exactly sure what kind of team you're trying to run. I'll just assume that this team is Balanced.
Movesets
I really don't have much to say about Frogadier and Milktank. Those are good sets.
Telling ya that a straight out Physical sweeper set is sorta wasting Mesprit's potential. You should have some support moves like Healing Wish (although a physical set is perfectly viable and the support move depends on what you need). I'm not sure if Power-up Punch is good on Mesprit though.
Remember: CAMERUPTITE WILL BE BANNED FROM NU (just wanted to stress that). The set should also be geared a little more to the offensive. Here's a good moveset (I still kept it a little bit defensive, since that's how you would want it):
- Flamethrower
- Toxic / Will-O-Wisp
- Earth Power
- (Filler - maybe Ancient Power, Protect)
A potential replacement for Camerupt might be (when ladder updates)...
Magmortar@Life Orb / Expert Belt / Assault Vest
Modest / Mild Nature
Ability: Flame Body
EVs: 252 Sp. Atk / 156 HP / 100 Sp. Def
Moveset:
- Fire Blast
- Thunderbolt
- Hidden Power [Grass]
- Psychic / Flame Charge / Focus Blast
This is a bulky set for Magmortar. The EVs give it respectable bulk. Fire Blast is good STAB, Thunderbolt and Hidden Power [Grass] is coverage. If you're running Flame Charge (for speed boosts) you should have Mild nature. Psychic and Focus Blast also provide further coverage. I would suggest Focus Blast because, although your Water weakness is alleviated, it also puts strain on your Rock weakness and Focus Blast is super-effective against Rock-types.
Note: The addition of Magmortar would also form a nice core of Magmortar and Electivire.
Togetic is more of a Defog support (I suggest putting Defog in there). Also it gets outclassed by M-Audino as a Wish passer / cleric. You could put M-Audino or normal Audino there if you want to replace Togetic (because your mega slot is open when Cameruptite is banned).
If you choose to replace Togetic with either M-Audino or normal Audino with Leftovers, follow this set:
Audino@ Leftovers / Audinoite
Careful (for Normal) / Bold (for Mega)
Ability: Regenerator
For Normal - 252 HP / 252 Sp. Def / 4 Atk
For Mega - 252 HP / 252 Def / 4 Sp. Def
Moveset:
- Wish
- Heal Bell
- Protect
- Filler (Toxic / Knock Off {for normal} / Dazzling Gleam {for mega})
Here I might suggest going for the normal Audino because it has less weaknesses and better synergies with your team. If you really want the mega though, go for M-Audino.
Your Electrivire set is great! I suggest that you should have Ice Punch > Fire Punch. It takes care of pesky Grass types that resist its STAB and kills most Ground-type Pokemon.
Another suggestion: Maybe Motor Drive > Vital Spirit? It better synergies with Frogadier because it covers Frogadier's Electric-type weakness. Electivire is pretty slow, so you can easily predict an Electric-type attack and switch out to Electivire for the free boost in speed. If you follow the suggestion of Magmortar (above), you already have someone to switch into a predicted Sleep Powder. It would be a good choice to choose Motor Drive over Vital Spirit.
Finally, I would change Electivire's item to something like Life Orb and Expert Belt, so you wouldn't be stuck using one move.
My Rating
Although some of your movesets need to be fixed and one of your Pokemon needs to be replaced, your team has a lot of potential and I can see it working well, especially in mid-ladder.
Good luck with your team!