Dangerous Fast Travel.

Fast travel having random encounters and enemy encounters based on path taken, sneak and survival. You can place intermediate locations to determine the path taken during the fast travel and your enemy encounters (based on enemies in the waste) should be more frequent for those with a poor combination of Sneak + Survival. This would make Survival much more important than it currently is. Random encounters would be much the same way but would be purely dependent on Survival and can happen anywhere.

I think I may try to make a mod of this when I get some time, if it's possible.

Gradual Inventory Weight

It makes no sense to have double your weight in your inventory and still being able to move about just as if you're only a pound over weight. Having next to no weight on your character should increase your speed and the gradual increase would decrease agility/speed accordingly.

moar bugs

I to want "full" implementation of the originals mechanics.

A full set of unique craftable, alternative weapons and explosives linked with survival, repair and science skills, then we could have a MacGyver build and something else to do with the excessive amount of bobby pins

Bear traps you can use like mines !

Flash light or improvised torch that can double as a weapon.

Death claw repellent stick or spray ! Makes Deathclaws run away with a turned up nose but attracts a stupid amount of mole rats. That's when you'll need the Mole Rat repellent stick or spray ! Which in turn attracts Death Claws

Same.

This could be done with a mod. I'd assume it pretty straightforward to duplicate and modify the mine weapon to use bear traps.
(The real impediment would be the need to add proper animations for every class of entity in the game that might step on one.)