The JD45 is the most interesting to me, particularly due to the extreme cost of the NerD for something I'm not going to be using that often. However I'm unclear on what current/future availability is.
Off center caps isn't a must have, I just have a keyset with off center that I can't use anywhere. And thinking more about it, I can likely remove it from my list; I just don't need a key that size on a 40% methinks.
I use SpaceFn elsewhere, hence why I would like a 40% that supports it: just easier to swap between boards. I also prefer SpaceFn to other methodologies I've tested. Not a deal breaker, just what's ideal for me.