This is just how I do things. Feel free to follow your own advice.
These tips will produce good-loking figures fast. Painting 6mm is increadibly fast work; they're so small that you can cheat a lot (which I always do ;-)
I use different kinds of acrylics, chiefly Citadel, Ral Partha and Miniature Paints (somewhere in my hidden past I was a fantasy player). I wash the based figures with the dipping technique to produce shadows, and to protect them. I spray the finished bases with Citadel matt varnish for even better protection, and to help keep the flock in place.
We bought a large sheet of 0,75mm thick steel from a metalworker, and got him to cut it up into bases for us. This is fast and cheap, and the bases are accurate, sturdy, and magnetic.
I previously used 1mm fibreboard, cut with scalpels along a ruler. Then I glued sheet metal to one side, so I could store the finished bases in boxes lined with magnetic sheets. I got this metal from cake boxes which I cut up using scissors, but other sources exist.
No matter the material of the base, I paint the base green or brown using cheap acrylics (or a spray can to save time but waste money) before I base.
PVA, both for fixing the figures to the base and for flock (the last with watered-down PVA mixed with a slight bit of washing up liquid to break surface tension).
Rule of thumb: 20 minutes per color per batch of 200 figs. This requires a correct state of mind: slap the paint on really fast. Never mind if you make small mistakes - the dipping technique will take care of that. After you've finished, you'll be surprised to note that the figures look good, anyway. I paint all my figures this way, and feel the look of my figures is very acceptable.
I.e. 200 Indian bowmen: spray brown, leave to dry. Paint white skirt, bamboo bow, light brown arrows, orange sword sheath, black hair, green ground. Each at 20 minutes gives a total of 2 hours for these 16 bases. (in actual fact, I use less time painting these Indians. Especially the sword sheaths and arrows take very little time).
The only exception to the above is general's elements, shield designs and standards. You'll often find yourself using much more time on these, and I feel this is justified as they do a lot for the general look of the army.