I am going to try and change the carry capacity from weight to available space.
Like instead of you not being able to carry lots of stuff because you don't have available room.
Things you are using like armor and weapons won't take up space.
So I am wondering before I try this will it be difficult? I'm very new.
First, I think it's a great idea!
How easy or hard is totally subjective though - new or not. If you are up for a challenge, I would say it's doable. I think both Richard8844 and Maegfaer have good points too... so maybe a combinatin of weight and space.
On a technical level, modifying the carry weight is pretty easy. The challenge will be as Maegfaer points out - how you will determine the size/space. If it were super easy, someone would have done it already. I would use this mod though if you finish it.