I would want a mod that makes you run slower backwards and when you're side-backwards running (diagonally, pressing s and d/a at the same time). In vanilla Skyrim I think this is way too fast, even though Bethesda said it would be slow when they released the game. I can easily "skate" by hitting, running backwards, hitting, running backwards, and so on... and basically become invincible to any enemy.

I think 30 % slower than it is in vanilla would be alright.

I wouldnt mind that either.

Don't combat mods already do this? If not, I can cook one up quickly that will also work on NPCs.

I use Duel and I haven't noticed running slower (nor does it say that in the description). If you can make an .esp I'd really appreciate it!

It is slower by default, not sure about going diagonal backwards though.

I know you cannot just run backwards and shoot arrows anymore...

And if you run backwards you should be able to trips and fall, that would be funny. In fact it would be funny in regular gameplay if it happened rarely every now and then.