My expertise in the 16th century is in early Elizabethan (as in pre-barrel hoops), not Tudor, but I will tell you that where your dress laced up showed off your rank- if it laced in the front it meant you had to dress yourself, lacing in back meant you had people to do that for you and were therefore rich. So if it's an upper class dress it's going to lace up the back. And to my knowledge stomachers didn't come in until the very end of the 16th century when the barrel hoops came in (if even then). The more open bodices at the end of the period could have developed from a doublet-like bodice that women could wear (in the early Elizabethan period that is), which buttoned down the front. I don't think that style was popular in Tudor times, the preferred look seems to be a bodice which laces up the back and has an uninterrupted front (of course many were decorated with trim and things but you know what I mean). But as I said, that's not my area of expertise.

Here's a great resource for portraits from 1500 to 1610:
http://entertainment.webshots.com/album/557253511xAShgE?start=0
(And here's the main page with albums for all periods- amazing!:
http://community.webshots.com/user/gogm1)

BUT, I don't mean to be a costume nazi. If it's being worn to a Ren Faire than stomacher or no you'll probably have a way more accurate costume than 99% of the people there.