With the current abundance of food in the game I'm surprised short rests are free. Surely like a 10-15 supply cost for a short rest, and forced 2x short rest before long rest unlocks leading to a total of 70 supply cost for a day.
I like this idea. Very much.
Agreed. I'd also suggest a relationship between rest cost and party size. Solo? 10 food units for long rest. All companions plus druid traveling companion? That's 70.
For the short rests, I'd swag 3× size of active party, so 3-12.
I'm not sure about requiring short rest before long rest, because maybe you think you're doing a minor encounter before a big one, and you're just unlucky.
Maybe a cleaner way disencentize long rests is to not allow them in unlikely locations. You have to be in the home base of the faction you're in good standing with, or in the wilderness far from baddies. Tollhouse is okay, blighted village is only safe if you're goblin-aligned or a drow, etc
Obviously that is (a) too complicated to implement, (b) difficult to make clear to players, and (c) defeated by fast travel, so it's an unreasonable suggestion, but I think it's better than requiring short rests before long ones.
+1
Perhaps instead of requiring short rests, if you DON'T short rest then the cost of food from those missing short rests is added onto your long rest total. This simulates such long rests actually encompasing you sitting around at camp for 16 hours, and only then going to sleep.
E.g., 2 short rests costing 10 food each, then long rest costing 40.
If you only take one short rest during the day, then the long rest costs 50.
If you don't take any short rests, then the long rest costs 60.
This could be modified so it's actually more expensive to only long rest, to simulate you only having to feed your party of 4 during short rests if you're traveling, but you have to feed all your camp members during short rests if you're just sitting around in camp. E.g., only long resting in the above example costs 70 or 80 total food, compared to the total of 60 if you use both short rests.
This encourages short restingt, but still allows for players to just long rest if they want.
Always +1 for restricting your ability to long rest (and teleport) in certain areas: e.g., Hag Lair, in the goblin church.