I'm not a "boot expert", but there are many good boots out there that would serve well for both alpine slogs and technical ice. You can find boots out there that are at the extremes for a specific climbing dicipline, but from trying on boots in the store and common sense evaluation, both the Nuptse and the Alphas are not at the extreme, and would work well for either. If you're really going to get into ice climbing, from what I have heard, you want a snugger fit (i haven't tried it myself yet). For plastics, fit may depend on what liner you go with (stock or third party) as well.
I ended up going with the Alphas because they are lighter, felt more precise, and yet they are more flexible than other plastics such as the Invernos, etc. I'm going to fit them with Intiution liners, and I think these will end up keeping my feet warm without the wieght and less precise feel of other plastics.
I'm sure that there are some nice leathers/composite material boots out there that are pretty comparable to the setup I'm going with. I've heard people say good things about the Scarpa Freneys.
I would go to a shop and try on a bunch of different brands to find the best fit.