Yeah, was thinking along those lines as well, but the issue there is that it quickly becomes a lot more complicated and bogged down in minutiae, in my opinion... While there is definitely a difference between "roughing it" and more luxurious accommodations, I feel like putting extra nitty gritty mechanics into defining different levels of rest quality could easily get hung up on the details and even be punishing for adventurers going out and, well, adventuring.
I absolutely maintain that there's always some roleplay value to finally getting a night in a posh tavern after weeks out in the wilds, and while it certainly would be cool to have some kind of extra bonus for doing that contra "getting by", I think rigid rules would end up getting more in the way there than with a more binary food/no food mechanic. Plus, for more comfortable (and likely expensive) conditions, you can probably just award inspiration as the cherry on top for kicking back.
In other news, more mechanical build nonsense: MotM Bugbear PCs have a Surprise Attack ability worded thusly:
If you hit a creature with an attack roll, the creature takes an extra 2d6 damage if it hasn’t taken a turn yet in the current combat.
Note the lack of specification on this needing to be a ranged or melee attack, or even a weapon attack... And also no qualifications for only using this once a turn/target.
This is going to be a variation of my "most annoying character to play next to" build, but this time it's actually a lot more capable of dealing some actual damage.
Bugbear Clockwork Sorcerer 15/Assassin 3/Fighter 2
Clockwork 14 gives the
absolutely nonsense Trance of Order ability, which lets you use a bonus action to enter the trance for 1 minute, wherein all saves, skill checks and attack rolls will count die rolls of 9 or lower as a 10. Assassin give you advantage against anything that hasn't taken a turn yet in combat, while also autocritting if you manage to surprise something. Fighter does action surge stuff.
So we enter combat, bonus action trance, then spend our two highest spell slots on Scorching Ray by casting and then surging to cast again. With an 8th and 7th slot, that's 17 rays.
17 rays, each doing 2d6 damage, plus 2d6 more thanks to Surprise Attack RAW working on spell attacks too for some ridiculous reason. Minimum attack roll of 10+modifiers, which with 20 CHA and level 20 means a minimum total of
21, before taking into account other bonuses like enhanced spell focus items. Plus they've all got advantage, which means a better chance of critting for
8d6 damage. And, of course, if you somehow manage to surprise an enemy then every beam autocrits. For 8d6. 17 times.
Again, this all hinges on not coming in dead last in initiative with your wimpy nerdling DEX, and also not going up against something magic immune/invuln globed etc... But, really, this is still just a thought experiment for throwing an obscene amount of dice on the table at once.