Overall it's becoming clear that ek7/warmage 4 is the build to beat out of my considerations. It gives a _lot_ of prepared spells and versatility without sacrificing melee punch. I do think Battlemaster looks fun, but not nearly as strong in the longer run. I'll have to save that for a ranged...
That's a great question I had not considered, honestly. The more interesting options right now might be:
1st Level:
Fog Cloud √- Situationally helpful, especially if ranged combat is involved.
Protection from E&G √+ Again, situational, but very good for those times when it is needed. I have...
So the other big trade-off or decision boils down to Warmagic (EK ability) versus Battlemaster maneuvers. Here, I think the controller aspects of battlemaster would be more fun, and would come on line much earlier (possibly by level three or five). Conversely, warmagic would not happen until...
I'll be going STR build, actually focusing on great weapon fighting.... not optimal for defense, but the archetype of a knight with a magical sword is my thang. [And the campaign has already started.] Dex based melee is a heresy ;)
War magic as a school... appears to really gimp defensive...
I'm in a Tomb of Annihilation campaign. I am considering the following builds that top out at 11. The goal is a build that will remain fun and effective for the whole campaign rather than just at the very end.
1) Battlemaster 6 / Abjuror 5
+ Maneuvers look fun
+ Solid, reaction-based spell...