For basic troops, I'd say up to an hour per mini not counting drying time for primer or layers of matte spray. I almost always paint in batches though, so that speeds things up considerably.
My standard is tabletop standard and is done as follows
1 Prime: Gesso or spray paint
2 Block colors
3 Dip (brushed on Minwax polyshades, very neatly applied and excess removed)
4 Paint Eyes and drybrush hair/fur
5 Matte Spray
6 Basing
Here's a couple of examples of my two most recent projects painted exaclty as above.
The Gladiators might have taken a smidgen over an hour as I was experimenting a bit and they have lots of detail. On the other hand, I'm working on some vintage 27mm Ventaurans figures right now. They are mostly in plain armor and I'm painting 16 of them in one go. They'll probably average out to about 30 minutes each!