If Ash and May were gym leaders, which Pokemon's would they have and what kind of gym would it be (Double, separate, the inside, etc.)?:
For Ash, I'd imagine something similar to Blue in HG/SS, with him just using no specific type. Probably would prefer single battles, and would probably be decorated to look like a power plant or something.
For May, she'd probably just take over from her father. Same gym. Similar Pokemon. All that jazz.