That's a good approach. I use the same principle, my mantra is 'why paint one when you can paint 50'!
Shouldn't really take you long once you get started either, I managed to collect, build and paint 38,000 pts in less than two years and still the forces grow bigger <rolls eyes> in fact my biggest limiting factor has been space, the constant re-arrangement of my shelves has become a fine art form and possibly an Olympic disipline! Need to approach this number of pieces like a machine, choose your pieces then run through them one stage at a time, a conveyor belt of one as it were. Try not to think, it only makes things worse :rolleyes:
With a force of this size base colours with strong lining will work well and as you say just a little extra work on the character peices as you see fit. Let's be honest a bazillion ultramarine symbols on all those shoulder pads is gonna make the best of us go cross eyed anyhow, we won't notice much else :D
Try and do some infantry then alternate it with vehicles to limit the monotony indeed it would probably help (if your intending to play) to plan a small average force size to paint first and get some decent games in, I found it has really re-charged my batteries and injected a little more enthusiasm where it had started to wilt a little!
Most important thing enjoy yourself!
Look forward to the updates :D
Bully