Dang! I meant to make it so you could select multiple and then provide your reasoning why you chose multiple. Oh well.
I prefer Hit Dice because that puts full strategy into the hands of the players. It also means you could have more short rests at higher levels when you might need them more - unless you get really beat up during a particular fight.
Imagine a player at level 8. They could take 8 short rests per day, spreading them out because they have 8 Hit Dice and could only use 1 per short rest. However, if they get hit hard and need to heal more after a particular fight, they might spend most or all of their hit dice in 1 short rest. Thus, not able to have as many that particular day because a single battle (or two) was really tough.
However, I would also not mind something else like a camping supply cost. I just think 2 is not enough and doesn't encourage short resting enough.
