Zardnaar
Legend
I would say, of those you listed, the top three would be: Dungeon Crawl Classics RPG, Old-School Essentials (specifically Advanced), and Worlds Without Number.
DCC RPG for the sword & sorcery, edge of your seat gonzo chaos fest. Based on 3E but mutated into a sort of B/X style race-as-class game. The best version of the fighter in any D&D-like game. Some of the best magic in any D&D-like game. And all the modules are top notch and ooze flavor.
Old-School Essentials for your reliving the glory days version of D&D. It’s directly compatible with B/X and AD&D. So everything published for them is open.
Worlds Without Number is the best single resource you could hope for to build a world and hexcrawl. Never even looked at the system.
I've been running 1E and BECMI adventures in C&C essentially unmodified.
Enjoyed C&C in the lead up to 5E after burning out on 3.X. Still enjoying it now and getting to use stuff I already own.