My Buy Time is between now and October. My monitors are dual 1680x1050. I look around first, but always end up shopping at Newegg, and I'm in America. I would put productivity software first, gaming second, small form factor third, watching/encoding video fourth and no blinking or glowing or neon lights fifth.
There's no reason you can't get that in an mATX build. If you wanted more memory or more than dual-GPUs, it could be a problem. I believe most mATX cases will hold 2 hard drives. It's really only when you get into the super small form factors that it becomes a problem.
See this Gigabyte board for most of what you're looking for on an H55 board, X58 or AM3 should be easier to find.