I would have a gym that would be hidden deep in the forrest, down a mountain. Nearby would also be a lake. It would be preety hard for trainers to find it due to the gym being concealed in mist occasionally. As far as pokemon types are concerned, I would use all because I find interesting like that. I would also use different areas of battle, like e.g. the lake, the top of the mountain, the dark forrest etc. so it I would be preety tough for trainers to beat. I would also forbbid the use of type advantage, because that way it would be interesting and more difficult and besides every gym has it's traps.:) Oh and I would have 3 on 3 pokemon battles, I think it's the best number of battles.;)
Oh and BTW I agree with you goofy_charizard_girl real pokemon battles are much more interesting than the ones in the games. Because I think it's unfair to the pokemon that it should lose due to his minor level than the level of his opponent. I think the pokemon's fighting should also depend on his personality, like if the pokemon is very persistant etc. and on the trainer abilities as well. Like a trainer could coach his pokemon to fight on and not give up..
Oh and BTW I agree with you goofy_charizard_girl real pokemon battles are much more interesting than the ones in the games. Because I think it's unfair to the pokemon that it should lose due to his minor level than the level of his opponent. I think the pokemon's fighting should also depend on his personality, like if the pokemon is very persistant etc. and on the trainer abilities as well. Like a trainer could coach his pokemon to fight on and not give up..