After thinking about this a little, I'm against powering up giants and non-dexy races. I'd rather nerf the things we think are too strong. So remove (or nerf) evade and remove (or nerf) STSF.
Wouldn't that about do it? Evade honestly doesn't seem like that big a deal, unless it's way better on 24/25 dex characters than it is on 23 dex.
How about this:
1. Evade only works on the attack/spell that starts combat.
2. STSF either:
a. Works the same except no "cutoff" effect, OR
b. Keeps the cutoff effect, but that's literally the *only* thing it does.