True Strike and Blade Ward would be broken as a bonus action. They're cantrips so you'd be able to use them every turn and just have permanent advantage or damage resistance.
As-is I actually do use True Strike with an Eldritch Knight Lae'zel occasionally. Whenever she's running at someone but can't quite make the full distance to attack I pop it and forgo a crappy ranged attack attempt. Then use Great Weapon Master's "All In" ability for two turns to make those huge +10 damage swings actually connect. It is also useful as a pre-cast when you know you're about to be in a fight so she can take off some heads right away.
I think it could stand to last three turns, though. Especially with how fast "turns" pass outside of combat, as I often lose entire turns when I pre-cast just because it takes a few seconds to move into position.
Blade Ward is useful when Wyll is surrounded or you know he's going to get hit a bunch before his next turn. The point of the cantrip is to sacrifice a turn of Eldritch Blast in exchange for reducing incoming and potentially fatal damage to more manageable levels. IF it needs a buff at all I'd just give it a two or three turn duration so it is something you can keep up by sacrificing damage every other turn, but I'm not convinced it really needs the buff.
