I use acrylics also, but what I do differantly is I use an ice cube tray for my brush rinsing water source. Before I start the days project, I stop in the kitchen and fill the tray with fresh water. As I'm painting if I use blue, then I ALWAYs have a blue water bin to keep my brush wet, or wash off the paint from the brush keeping the brush clean even during use preventing dried paint to mess up my lines. I always roll the brush on a paper towel to see if any more color comes out after I'm done with that color and just when I don't see any color showing on my shop towel, and think that I'm only seeing water, then I rinse the brush out in one of the clear water bins on the ice cube tray, just for good riddens, and from that point on that particular bin will always be my final rinse bin untill it gets kinda dirty. I like it this way because if I have 4 colors going in a short period, I have clean water for each color with the ice cube tray.
As for mixing my paints, I use the typical artist mixing trays that you can buy at your neigborhood art supply store or craft center. Because the paint is out in the open air I without fail pour a drop or two of RETARDER to keep the acrylics from drying out to fast. There's 10 little dimples in the one that I use, it holds plenty of paint for a session and I found it to be advantageous to wash that sucker out in the sink when I'm done for the day. If you don't, not a biggie, Andrea and Vallejo's paints even when dried will come out if you soak it with hot water and use one of those green abrasive sponges. For the most part, you'll get it so clean that you'll have it looking like the day that you bought it. Recycle! LOL!
For metalics, I found a method of using Humbrols metalizer for my shinning silvery things like swords. If you apply the stuff with a brush, add just a tad of thinner to keep it flowing, work fast, get it smooth, then as soon as you see it start to turn a differant color while drying, start buffing it right away! You're cheating certain death here so practice, but when I brought my figure to over a half dozen shows and people thought that it was a metal figure and not the resin figure that it was...I was sold! Trust me though, it took lots of practice and mistakes to get it down right. I think I'm going to use Gunzie's metalizers now, I hear through the grapevine that the metalic flakes are so small that you can't see them on smaller figures. SO, as soon as I can find some, I may switch.
As for my use with oils, I think oils make wonderfull washes, I love to use acrylics as a base, shadows and highlights on faces then use oils for warming up the face, on top of the acrylics.
Good Luck
John (Aka) EasyOff... da figure strippa!