Fire Out
Water
Att: 60
Acc: 95
PP: 15
Can also be used as a HM. It KO's Fire Pokemon. Outside battle, you can put out a fire on your way
It's too powerfull move, i think, they can't KO Fire pokemons but can do more damage for that type. If you want can KO fire type with that type, give them low PP, low Accuracy <like 50%> and they can't does damage. Idea with new HM it's maybe good, but there are now 3 water HM, they maybe can be ground type.
I think maybe Wichu can change Field Effect of Hypnosis, they can controle wild pokemons mind's and can move it if they block a way and/or change Field Effect of Dig, they can dig tunnel when ground is sand. They don't be needed to end game but give ability to explore some additional area with move tutors, rare pokemons and items. Dig also can give you ability to visit undeground, prehistorical caves... but you can do that after fight with trainer Old Miner <they can use prehistorical pokemons>. That battle can be after win 3 badge.
Item:
Mythic Rock - instead of Hearth Scale, Mushrooms
In that caves can life basically evolution form, wild prehistorical pokemons with randomly levels 1-30 (95% for one pokemon kind, 5% for another one). You can return to surface only with rock stairs, which come in place when you use Dig. You can find pokeballs with random items in caves, bury through other trainers. They can be some events with NPC like "I don't remeber where I bury my HyperPotion" <or maybe pokeball with pokemon :D>. If you return him pokemon for him, they can you give mysterious item, which you can use to wake legendary pokemon. There can be only random place in maps when you can use Dig to go to caves. In undergrounds place you can find randomly rare (which you can find only in underground) hidden items (like when you use itemfinder) like evolution stones, Mythic Rocks, Shards, Rare Bones, plates and other (i think, all of that items are very old). "XYZ find strange item is soil. Do you want check it?" <Yes/No> "Oh! It's ______! Do you want take _______?" ;) After league you can give 10% chance to find underground "room" with only... one Regi!!
Yes, i know, that can be D/P plagiarism, but propably all D/P players remember that excite undergrounds mining and there is some different, new, another method like in D/P. Good locations for Regis and prehistorical pokemons and good encouragement for use Dig move in game. :D