Lots of questions, Joe! I'll try to answer several...
The final 400: Last time I went up, one hiker was too nervous to do it. While the rest went up, he stayed at the notch, and even lost his cookies there. On the way back down, he crab-crawled on all four some of the way down below the notch. Everyone else just walks it. Going up from the notch is mostly a no-hands climb, sometimes you can reach out and touch the rock for balance. It is not hard for those comfortable with heights. But I am worried since you had trouble on the E-ledges. I think the climbing gym stuff might be a good recommendation.
I have never day hiked the MR. But I have seen others say it takes about as much time as the main trail. But I think it should take less, since you don't have those interminable switchbacks.
I wouldn't take ropes -- if that is what you need, it would take a multi-day, due to the extra weight hauling. If you hired a guide, that is how they would do it.
If you day hike it, start in the dark, but first familiarize yourself with the route up to LBSL so you can do it as dawn breaks. As for route finding, check all the links in the
Mountaineer's Route info links within... (It is linked in the first paragraph of the Orientation Notes).
