Since I'm not spellcapped 30 agi & 20 hit outweights 40 agi by about 2 EP, but had I been spellcapped 40 agi would have been stronger yes. And since haste has higher statweight than spellcap for combat, the same goes for my offhand ^_^
And indeed spellhit is the second best secondary stat for me to go for atm, but it's not better than haste so it's unwise to go out of ones way to reforge into it, unless you have a weaker stat + haste on a gearpiece.
And as for the spec, there's simply no place where I need blade twisting in FL, the only other option (for me) would be Imp Gouge for the occasional Sinestra runs.