I have them all (plus a lot more). 28mm f2.0 is great lens. Sharp and contrasty even wide open. But for wide Nikkor lenses, I prefer 24mm f2.8 over the 28mm.
Originally Posted by msbarnes
50mm f2.0 is probably the best 50's. I have a few faster 50's but f2.0 is the best.
There needs no explanation about the legendary 105mm. I have both older Sonnar design and new DG design. The sonnar is tad softer but has smoother bokeh. Both are fantastic.
Those 2 20mm you listed are not in the same league as other nikkors listed above. Except older 20mm f3.5 UD which is great lens. 20mm f2.8 is the best among 4 versions of the 20's.
Other not expensive but good lenses are:
35mm f2.0 AI - My go to lens. Always on my F3
85mm f1.8 - All are non-AI. Brilliant.
180mm f2.8 ED - legendary. Little pricy.
200mm f4.0 AIS - if 180mm is too much for you go for this lens. It's as good.
55mm and 105mm micro Nikkors are stellas too.