I have a bit of nostalgia for AIWC, particularly the last of the 3.8.x releases (Unity's been great, don't get me wrong, there's just something about some of the mechanics that shifted to 4.0 that I feel wistful for the Old Ways), but in general, yes, the new game is fantastic.
I definitely want to get in to the code at some point and do some modding (more galaxy types, maybe some AI stuff), but I need to find the time first.