I'm nearly 40 and a petite size 10 with a small bust.
I'm off to a posh do where I need a ball gown type dress.
Don't want to look like I'm off to the prom 20 years too late, so I'd prefer not to have anything too meringue like 
I need something that isn't too low at the front or strapless as often necklines are designed for taller people with bigger chests.
I've got dark brown hair but am quite pale, so don't think nude or pale colours suit me too well.
Any suggestions?