Concerning MF, I can only agree with John Koerner :
1) get a DK-17M. I have these since my D700 times (2009), then on D800, now on Df.
2) practice, practice and practice
I do not (yet) feel the need for another focusing screen.
Concerning lenses, if macro is important and frequent, maybe get a macro lens for ease of use.
The 55/2.8 is nice, and I have many keepers shot with it and either a FF Nikon, or a m43 Olympus with adapter. I do not remember cases of outrageously disturbing bokeh, but
1) beware of oily blades (cases reported by B.R.) - when testing, also shoot series from f/2.8 to the narrowest and check that the illumination remains the same (but for vignetting)
2) contrast is relatively mild. Easily corrected to your taste if you want it strong, but...
Concerning the non-macro Nikkors, my vote would go to the 50/1.2 AIS (= 9 blades).
The 50/1.8 AI is fine, but for some reason I never got enthusiastic about it. At wide apertures, the 50/1.2 beats it (but for distortion). For general photography, I feel more attracted by the 50/2 that seems to have more character + no need for a hood because of the recessed front lens, a useful feature when travelling. Call it a confidence builder. Bokeh can be *very* busy, but not disagreeable.
The old 50/1.4 SC can have busy, painterly bokeh. Otherwise the handling (non Ai !) does not make it an allrounder.
The Summicron R (with Leitax mount) is mechanically and optically excellent and could suit you, but it is even more manual (no aperture lever). Try it if you can find one. Slow photography only. The full aperture is quite usable, albeit not at the level of the "M" summicrons. Otherwise, a broadly aberration-free lens with good bokeh. Amazing.
Well, in terms of macro, sharpness, contrast, bokeh, nothing beats the Zeiss 50/2 (and the price is out of sight). By all means get the Milvus version (better coatings) if against-the-light shooting is important to you. It is rather big and heavy, but does not trade quality for universality. Its short focus throw between 5m and infinite is compensated by the rather firm, but fluid (i.e. no dry friction-feel) and slack-free focus ring movement. I was lucky enough to find a brand new second hand copy...