Great photos, Chris, especially the first and fourth.
I can't get HP5+ to work properly in Rodinal although I can with Tri-X. The latter works superbly well for me using the technique advocated over the years by Don Cardwell on APUG (very very gentle agitation every five minutes).
Years ago I very much liked HP5+ in straight Microphen, mainly cos of the highlight detail it preserves and the superb “colour” it gives the grey tones, but it’s at the cost of losing a little sharpness, although, for me, that disadvantage is fully compensated by the tonal gains. As an alternative I used D76 1:1 and it worked well, giving the snap that I sometimes appreciated.
I tried Microdol-X and, later Perceptol, in various dilutions but couldn’t get that great tonality that Erik van Straten gets with a variety of films, including HP5+, using I believe diluted Perceptol. Looking at his photos I realise that I should have tried harder!
We mustn’t forget that the best technique for any individual will also depend on whether development is primarily for scanning or printing. (My comments above refer only to printing).
Anthony