Personally, if I'm wanting "free" power, I really don't see why I'd go beyond a hell pump with some geo-gens. 20 EU/t, which can be easily supported by cheap copper cables, multiplied by however many geo-gens you can build and/or pack into your power room. Get a stack of them, and you've got 1,280 EU/t, and the only real show-stopper there, in terms of cost, is iron which, with a few pulverizers and some elbow grease, stops being a problem pretty quickly. I'm kinda torn about solars. On one hand, making them more expensive does make them a bit larger a goal, but on the other, requiring UU-Matter seems a bit arbitrary.
Honestly, instead of mucking the solars, IC2 et al should be buffing the other mid/high-tier options to make them more attractive. I, for example, would probably never bother with a fusion reactor. I've never needed that much power, and not only is the creation cost high, but simply getting the thing running requires an asston of power to the point where only one or two fuel types give you any net gain, and even then, if NEI is to be believed, its not all that great when compared to cheaper, simpler forms of power production. Make the other options cooler and more attractive!