Hmm, sad to hear we can't trick the game into consuming more than one resource per ship/station. I was thinking of doing something like having the traditional fuel reactor have a high energy output and a minimal energy storage capacity while the maintenance reactor would have a minimal energy output and a high energy storage capacity, but if you can't mix and match stats like that and/or the game would only burn fuel in one of those reactor types anyway, then I guess that's that.
As for DW2, until the game is actually announced or rumored by a credible source, I will assume that it's not in development. Seeing as I'm primarily a Civ5 modder, this is usually when I'd say that DW:U would benefit from releasing its gameplay source code to modders, but I know that DW:U doesn't have its code split between engine and gameplay parts the way the Civ series has had since at least Civ4, and reorganizing a codebase like that be quite a huge effort. This isn't even talking about sorting out copyright stuff with the legal team, e.g. I know that the Civ4 lead designer had to deal with 2K's legal team for quite a bit before all the potential legal issues were sorted out with publicly releasing a major part of the game's source code.