Thanks for the suggestions everyone! I should have made it clear in my initial post that I wasn't really interested in metal cages (that's kinda what I meant by "I do want the bottle cages to look like they belong on a modern carbon frame road bike") but would definitely consider them for a touring bike etc.
RGMN I actually had Bontrager Elite cages on a Trek I used to own, and I don't recall ever losing any bottles while riding that. Thanks for reminding me.
chaadster The Elite Custom Race+ was actually on my radar. Thanks for mentioning it!
I'll look at the other suggestions too. Thanks all!