Vne, Va and lift?

I wonder, does anyone routinely recalculate limiting V speeds on the
basis of TOW? I assume that limiting Va speeds go with the square root
of the fraction MTOW loading so for 75% MTOW Va would drop to 86% Va.
But the question is, if Vne is limited by arodynamic issues such as
flutter or windshield how would that change with load? Put another
way, is Vne ever load dependent and/or does anyone use a rule like
that for Va?

A second sort of connected question is: is there any wing that can
produce more lift at 45 degrees AOA than at the stall point (I know
that most airfoils produce about the same lift at 45 AOA as at the
stalling point)? What I'm thinking about is wings with washout or drag
reducing devices that will reduce maximum lift at the stall point but
not the 'flat plate at 45 AOA' lift. Put another way, how much loss of
lift do we get from typical washout?

Cheers