1) There's already a huge variety of Wild Pokémon anyway so I don't think that'd really be an issue if I choose the types properly, but I agree it is more labourious to implement than it appeared at first sight. Mostly because I have to do a load of file swapping, text changing, script editing etc to get it to work correctly. I might well just keep it the same, since I'm probably going to want to focus my efforts on BB2VW2 once I've got this fixed of its bugs.
2) Well, in the next version I'm intending to make it so whenever you receive a TM, you get 99 of it to give a psuedo-feel of infinite use TMs (since I can't seem to actually get them to work like they do in BW). Due to that I'll be removing them from the markets so that means I'll have plenty of spare space to put in extra items such as berries and evolution items, so yeah, that should work out pretty well actually. Though not many people need doubles of particular Pokémon, I gotta say o-o;
Hi Dray thanks for answering!
Have you tried to turn TMs into key item equivalents? This would make them infinite use.
Also, if you don't have space for items in shops, you can give the evolution items as hold items to a few select wild Pokémon like what happens with Magmarizer, Dragon Scale, etc. (which you can get in the wild, though higher chance to get them would be cool!). It's just a way to keep them infinite. And, well some people like having double of each Pokémon, because of movesets and different EV spreads.