In my old career save, I had a few tested, rated lifting subassemblies, with descriptions saying the highest weight and altitude I'd used them with (including one that was rated for X tons to Munar orbit). In my newer save, I've been doing a lot more space stations. Those tend to get more one-off assemblies, with the exception of smaller pieces (Station Science experiments, for example), which I had just saved one of, and then made new ones with different experiments by loading the saved craft and swapping out the experiment module. Also, now that I've started to use the KSO in LKO, standardization is much easier - I load my custom KSO craft, and just swap out payload.
In many of the current IVAs, the seats have really limited fields of view. Is there any hope of you unlocking them so the Kerbals can look around more? I'm especially wondering for the cupola, where currently it seems like none of the seats can see out of the big top window.