Brunch cocktails beyond mimosas and bloody marys?
Corpse Revivers are going to be difficult to find on a menu, but you can get interesting, lighter cocktails at a few places, such as:
Fatty Cue - brunch cocktails list is longer than what's online when I've gone, and the bartenders are fairly comfortable going off menu to make classics
Saxon and Parole
North End Grill - their brunch cocktails list isn't online, unfortunately, but from what I observed, they are aiming to do serious cocktails.
I think what you really want, though, is Clover Club in Brooklyn.
The Beagle is also reopening soon, not sure if they'll still be doing brunch, but their previous brunch cocktails menu is probably the most ambitious I've seen in Manhattan for the day time.