Prakriti
Hi, I'm a Mindflayer, but don't let that worry you
Yeah, I'm definitely going to use Slow Natural Recovery or Gritty Realism if I run a hex-crawl in 5E. Otherwise, why even have random encounters?This goes especially if yo ugot hard resting rules 8hour short- and weekend/1week long rest e.g.
Sadly, though, neither of those variants perfectly captures the flavor of AD&D, which is what I would want to get out of an exploration-heavy game.
Maybe Slow Natural Recovery (i.e. you don't gain hit points after a long rest), plus a reduction in the number of Hit Dice you regain after a long rest -- maybe 1 instead of 1/2 your level. That would make random encounters a lot more consequential.