At my peak I was running a modified 5BR set with over 14,000 infra, proven by the fact that I own a Scientific Development Center. To be honest, I've never even considered what resources I would select for myself. Likely Uranium (since I'm one of the few people in my alliance that can have nukes, it'd be necessary to have a constant supply to make up for it) and one of the 3BR/5BR crossover resources. I'd set myself up for infra buying till I hit like 8k+ or so, then switch over to an income set and start banking all kinds of mad cash.
Been there, done that, got the t-shirt.