I've made some progress on the Hardrock gravel/do-it-all build:
I replaced the crappy Force brake levers (which also had the wrong pull ratio) with a pair of Tektro RL520s and also got rid of the old bar tape that had been reused several times while I was figuring out the position of the levers and no longer felt very nice.
The 11-36t cassette has been replaced by a 11-42. I did buy a cheap one which means it's really heavy (630 g, more than the NX 11-speed cassette) and the RD hanger extender means it's doesn't shift very well, but it gives me the range I need and I'll eventually get rid of all of this anyway when I have the money for a proper 12-speed setup.
I've now done about 220 km on the bike and I'm really happy about the way it turned out. I do still need to get a slightly shorter stem (probably a 70mm instead of the 80 I'm using now) because the handlebar feels a little bit too far, but I can already spend well over an hour on the bike every day without any significant discomfort.