Are there any other concerns I should have by having a calibration Library?
Hard to say. You're venturing into territory I usually don't go. That means you get to let us know how it works.
Generally speaking, it seems to me that the most reusable frame is the master bias per your ISO. The only thing I can think that could go wrong there is the master is too out-of-date, or, whatever you are trying to calibrate now has different RAW settings. Sometimes that happens: For example if you underexposed and need to bump the gain so DSS can even see any stars, your master bias created with normal RAW settings probably doesn't match now. Recently, I changed my default DSS setting to have the no WB box checked off. So, I had to create a new master bias, which I can do as the subframes were also still stored away.
Master darks and dark flats probably come next. Same concerns as above, but also add in whether or not a bias frame was used in their creation, or not. Also temperature - not always possible with a lot of DSLR's. In fact at the moment I am not using them as I can find little improvement. Will see if that holds into the summer temps, or maybe I'll start trying LENR. For now though, I'm just stacking lights, flats, and bias.
Master flats I would put last as far as library capability, for all the previous concerns plus dust motes and possible vignetting orientation. Here's the part I don't know yet - at some point, DSS scales the flats (or master flat) to the lights. Now, is that done during creation of the master flat, or during stacking after the master has already been made?
Being unsure, what I have done is actually just duplicate the flat subs from a different session (same ISO and exposure) into a new folder, and then let DSS register and stack as if they were new flats taken for that purpose.
Best thing for reuse and library though is to have all the details and settings noted, and maybe also archive DSS' info file with it, in case you need to open it up and look.