Water types are everywhere and Flying types are fairly common as well. Plus, it's the best way to take down Gyarados without using Celebi and Grass not and gets unresisted coverage with Ice (another amazing attacking type) except on Magnezone and Volt Absorb Lanturn. Why do ask all of these silly questions? Why not just try these things out and see if they're any good and if they are, post them in the New and Creative Movesets Thread?
All Pokemon that can learn TMs besides Regigas can learn Rest and they aren't Psychic. Agility often has more to do with high speed than being Psychic and other moves are like this too. For example, all Electric types can learn Light Screen and many Fighting types can learn Meditate. I'd run ThunderPunch because Gliscor can be hit neutrally by Meteor Mash and is countered fairly easily by Bulky Waters and Zapdos gets hit SE by Stealth Rock. Rotom-A is annoying but Zen Headbutt seems more like a liability to me than it's worth.
I have an idea-I'll do the same thing when I couldn't decide what last move to give SDLuke-I'll clone three Metagrosses, give on Zen Headbutt, one Ice Punch and one T-punch :P...
Personally, what would you use?
Also, is Agility a real Psychic move? Metagross is a secondary Psychic and gets it, Deoxys also gets it and is Psychic, but also quite a few non-Psychics...then again, Suicune and Kyogre naturally learn Calm Mind, and Ariados Psychic, and both are still the most known Psychic-type moves...your opinion?
"I'm not sure if anything could even take the first or second Rollout so there would be the problem of KOing all of the opponent's Pokemon before you get to the 10th Rollout."
Thread got locked, but I believe it's even worse. Metronome only acts on move selection. Meaning it's not ten Rollouts, but FIFTY!
I think they are, however, just about survivable. The defender should use multiple max+ Def/HP Leftovers Steelix with Rest, Sleep Talk, and Harden, and provide Reflect support. (Baton Passing Aqua Ring may be worthwhile too). Pure Power should also be skill Swapped onto Shuckle as late as possible.