In a similar, but more time/child constrained situation (if only twins and other small children could do the grunt work...) I ended up settling for a quality dark brown paint.  Sanded like a maniac between coats and then waxed (again, if only 3 year olds didn't eat wax...).  Not my inital goal, but not wholly intolerable either.  Went w/this after examing lovely high-end childless pieces that had the look I wanted and shrugging the difference. 

I am having the same problem with a piece of furniture I'm working on... Tried several coats, but I just can't get that dark, modern, even look. Urgh, so frustrating!