You pretty much nailed my big reasons as well. Especially things like:
Chargen: not only fast and easy, but you didn't spend all this time making your PC awesome before you even played a minute of the game. The gameplay is what makes your player awesome, not chargen. It's the whole zero to hero preference.
Yup. In the long running B/X game I've been running (about 6-7 years now)... the fighter in the group (level 6 now) was just wrecking house... I commented that his character is pretty bad-ass and asked what his strength was... the player responded 13 (respectable, sure but surprising to me).
His character was a bad-ass because the player played him like a bad-ass... took chances, went all in when warranted. It wasn't the numbers on the sheet it was the way it was played.
Random magic item tables: What's that? you found a magical battle axe, but your PC uses a sword? Well, that's what was there, because the last person to use it used a battle axe. I prefer more living world than one where you change and cater to PC wants. I almost never change found magic items just because it's what a PC wants instead.
The other side to this is there isn't as much specialization, so your PC can probably just pick up the battle axe and go. The character didn't have to invest 5 feats into being good with the sword.