That's how a minecraft desert looks like.This makes desert wells being pointless.They need to be actualy deserts!Minecraft deserts has like 12371927 water lakes!To fix that remove all lake generations in the desert and add a rare structure(rare like the desert villages),the oasis.Other thing that make the desert harder and make it looks like a real desert it's make the twice as fast hungry if there isn't block above it,and add a thirsty bar,that only appear when you are in the desert.Other thing is make all water in loaded chunks evaporate in 3 minutes if there is no block above it,and in 8 minutes with a block above it.Make deserts larger,and make they have high generated dunes,making hard to cross the deserts,forcing you to jump and make you hungry.Make rarely,rarely,rarely rain in the desert,making useful catch rain water with cauldron.That will make the game harder.If you don't want the game to be harder play in peaceful!=D
Actually hardcore is too easy,if you alredy know how play.
Only thing i support in here is to cut down on the water resources,plus there is rare structures in the desert Like:Pyramids, and wells(you can say uncommon).
There is a lot of positive changes here. Less lakes would be swell, and the oasis sounds like a cool idea. As for hunger, i would rather it be not such a drastic change. Make it 1.5% so spawning in the desert wouldn't be such a death sentence. I don't think water should evaporate. That would be making it a bit too hard. Deserts should stay the same size. Dunes would be an interesting idea, but I would rather have them spawn more rarely. As for the rare rain event, that would be very cool. 4/6 support.
They sure do need improvement, but not the way you said it with the faster hunger and water evaporation...
But the open water limit sounds good, along with the rare rain.
On the fence with this idea.