One-handed and two-handed melee, as well as shields and dual wield.
Sounds a lot like the ENG, doesn't it?
All I'm saying is, that every class needs weapon classes to specialise in, and shields on the ENG seems like one too many.
Would be great if they were replaced with more Cannon based skills.
If you're making a Paladin with Shield based skills, go all out, and let the ENG be the heavy weaps specialist.
Bringing something new to the vanilla classes won't upset too many, in fact I'd like to think it'd reinvigorate them.
I'm a theme freak, I know, sorry :/
Adding a defensive apsect to SnB might be a good start perhaps?
Lvl 15 is also what, 90% of Shield Armor, right, little low hey...