This is grainy film - no way around that. As such you should focus on tonality and acutance. Realize that the nominal asa is closer to 1000, not 3200. If you want good tonality, rate it at 1000. Someone has already rightly pointed out that low light scenes are inherently more contrasty than not. Attempting to squeeze more film speed with extended developer times will lead to insanely dense highlights, blocked middle tones and no increased density in the shadow areas.

I used to have a job shooting this stuff for aerial night photography. The preliminary part of the job was to test it with numerous developers. Surprise!...I discovered that compensating developers gave negs that yielded the most pleasing, easy to print results. At the time Cachet AB55 worked best(since discontinued) , followed by dilute ddx (gentle agitation scheme), and diafine. Now I prefer rodinal stand precisely for these reasons - eminently printable and razor-like acutance. There's really no point in using fine grain developers with high speed films like delta 3200. The results will look soft and blotchy.

Now, at some point you'll have to stop asking questions about the myriad developer formulas and try it out yourself - either shoot or get off the pot!