But there's
always more stuff, and interactions unfound 'til now ...
Allied Defense, from Shining South, synergizes very well with Active Shield Defense/Robilar's Gambit. Since you're routinely pulling off the maximum possible for Combat Expertise, you might as well grant that bonus to adjacent allies as well.
... speaking of which, toward the end of 3.5e there was a feat (?) or something
perhaps in The Forge Of War, that gave an extra attack under certain conditions
to someone with a Shield. Maybe a +1 mod.
Caelic and I discussed it rather shortly. Alas idk any more
Titan Bloodline 12 ability works with shields or the onehand wielded weapon.
Good stuff.