As you can see from this shot, the floor passes under the wall... should I cut a strip and texture it with caulk or does this even matter?

Miter brushes whenever you can.

As P.C.Invasion said, that is the correct way to do it, you should get into the habit of always doing it this way.

The reason being if you add up all them edges that have a texture on them yet cant be seen at any time, then you are wasting a lot of rendering time and making the engine work harder than it has too.

omg, I never thought of that. I already tapered my wall corners but now I see how you have the floor and ceiling done. I will fix all that for sure. I've play tested my map quite a few times and so far no dips below 91fps. This will most likely make things even more smooth...

Thanks guys this help me a lot.