I noticed all the blog folks advocating training of destroyer/BC and all the racial cruisers to 3 for max skill point return when they do the skill changes. The latest I heard (rumor) was March for that to happen though. I have BC4 on all but my main (who has BC5) and Destroyer5 on everyone along with all racial cruisers at least to 3. BC5 is a little too painful to bother with right now for my short term goals, but I may do it on a few more of my alt accounts.

They did change TONS of ships in this last expansion and I have pirate buddies running around killing battlecruisers in the new mining frigate now. Lots of improvements, especially from the logistics angle where you don't need T2 logistics cruisers to provide useful logistics to your fleets.

I use a single machine for all toons. As long as you run clients for performance you'll be fine from what I've seen. I do use isboxer for pve missions, but thats about it. I don't find it terribly useful for the stuff I'm doing now, but if I decide to bring in more alts to pvp I'll definitely be using it there.