well, for most things you mention really it does not matter. However you can save a lot of time later when you do it all before resizing ... just in case you need the original size at some point with all the changes applied
Sharpening should always be done on the final size though.
It doesn't matter at all. On full weddings I adjust and then resize, and on portraits (bridals etc) I crop and then adjust. It shouldn't make any difference.
EOS-
Watch out for sharpening. It MUST be the last step before print. On most web images I bypass that step as it halos. But when I send out photos for reprint, I crop and then blast it with KPD unsharp.
I might work differently from others but I do an initial (light) sharpening along with any global changes (temp, color, brightness, exposure, etc) before I do any pixel level changes. After pixel level changes, I do snapshot then slight area sharpen (USM with tiny radius, 0 threshold). Then save as PSD.
If I am going to print I size and do flnal area sharpen, smart sharpen, convert profile, convert to 8 bit, save as jpeg.
If I am going to display on web, I reduce size, convert profile to sRGB, convert to 8 bit, resharpen and save as jpeg