Blue Shallows, Dark Depths

I have long been fascinated with Original Dungeons and Dragons, but I've also long found it confusing. Late last year, I decided to put my head down and figure it out — by running my own solo game.  Honestly, this has been more difficult than I originally imagined. Much is left up to interpretation, but I've been trying to meet the game where it's at. In that vein, I've been thinking a lot about the game's classes. How does one change class if they aren't an elf? Why is it not recommended, aside from the prime requisite requirement? Why can clerics not use bladed weapons? Why can't human magic-users wear armor, but elves can "use magic armor and still act as Magic-Users"? Looking closely at the elf type description, I get even more confused. They can freely switch class between adventures, but they gain the benefits of both classes? Then... why would they need to switch class at all?  I've seen this interpreted as elves needing to choose which...

  E veryone is trying to find a way to stop making multiple dice rolls just to make an attack in D&D-style combat.  Well, okay, not everyone, but certainly it is discussed a lot. From the "auto-hit" of  Into the Odd - style combat, to the more recent exploration of the "Kubular method"  of attack rolls by Marcia B. of Traverse Fantasy, and many more discussions in between, many of the best and brightest of the old-school and adjacent scenes have explored the idea and continue to do so.  I am certainly not one of the best and brightest, however, I have been thinking a lot about this. My issue is twofold: I like making as few dice rolls as possible, and I hate numbers. Even basic math, if needed regularly, takes me out of the game. I know this is a personal problem, but hey, doesn't all good innovation come from tight constraints? Probably not, but whatever. In a new rule system I'm tinkering with, combat is resolved by a single roll-off between the attack...