I'm assuming this is for in-game purposes.
One thing you could do with here is a HM Slave. Most of the HM moves (with Surf, Waterfall and to a lesser extent, Rock Smash being the only real exceptions) are typically poor moves in battle. As such, you may want to remove them for more effective moves. Bibarel is a brilliant HM Slave, so if you have one, consider dumping some of your weaker HM moves onto it to free up slots on your team members' movesets.
Moving on:
- Infernape is alright, but Return isn't really necessary since Infernape has very nice type coverage, and Return doesn't really help it in that area. A good Rock-type move can work, and Grass Knot and ThunderPunch are viable options as well. Cut can also be dropped for another move, possibly Swords Dance from the Game Corner if you have the money for it.
- Lucario really needs to drop the HM moves since they squatter its biggest strength: its enormous movepool. With moves like Psychic, Aura Sphere and Dragon Pulse on the special side and Close Combat, ExtremeSpeed and the elemental punches to bolster its physical movepool, Lucario's coverage is second only to that of Mew and possibly Rayquaza. Since both of Lucario's offensive stats are very impressive, mix and match the available moves and make a set that you like.
- Leafeon doesn't need Magical Leaf, since Razor Leaf runs off its superior Attack stat and already gives you a STAB attack. Swift also is of little use since it also is a special attack. Good moves for Leafeon are Aerial Ace, Swords Dance (again), Return and X-Scissor if you can get hold of the appropriate TMs. I'd keep Synthesis though since Leafeon can take hits decently.
- First of all, I hope your Togekiss has Serene Grace. If it does, Air Slash is a must for the 60% chance of flinching the opponent. Moves like AncientPower, Ominous Wind and Silver Wind are also good to have for boosting your stats. Aura Sphere is also a good move to have for its never-miss function.
- Muddy Water is decent for Gastrodon since the Accuracy drop to the opponent combined with the damage the move does (same as Surf, which rocks with 95 Power) makes it deadly if luck is on your side, and still good even when it isn't. Having both Surf and Muddy Water isn't worth it though, so have either one or the other - typically, having two attacks of the same type in a moveset is a bad idea, so avoid it as much as you possibly can. Recover at Lv.54 is a must-have.
- Your Froslass is quite good actually. Blizzard never misses when it is Hailing, so I'd definitely go for Blizzard here, although if the PP drop bothers you (combined with Ominous Wind it may do) then stick with what you have so far for your Ice-type attack. Crunch is somewhat obsolete since both Ghost and Dark-type moves get identical coverage, so swap Crunch with either Psychic or an Electric-type attack if you want, or even a disabling move like Confuse Ray for a more methodical approach.
