I'm happy there is now a little "+" button in the MAP creation area of LWM, simple, effective, and FAST.

But I'd like there to be more use of Selection sets, and in particular I'd like Edge Selection Sets.

This video detailing C4d's version of selection sets pretty much says everything:
Let's steal that stuff!

A feature I'd like to see added to LWM, if it can be done in a FAST way that doesn't use crazy amounts of memory, would be a scrolling window of ALL the selections the user makes: iow, every selection you make generates a temporary selection set in a scrolling window, whose length (depth?) is user definable (to ameliorate memory issues). IOW, a "Automatic Selection History". For one thing, this would make creating permanent Selection sets easy, as just clicking a "+" next to a selection entry would add that set to the permanent list.

Each entry would be preceded by a Point/Edge/Poly icon to signify which kind of set it is, and double clicking that set would a) switch to that mode and b) Select that set. Boolean type operations could be either RMB menu or bucky key, or both.

So, a user could easily go back, say, 20 selections, very quickly.