Any idea what tire size would fill the top of the arch better ?

I don’t like that gap above the tire between the arch

I’m thinking maybe going 70 profile like a 255/70/15 ?

Below are pics of it with

15 x 8 (I think)
5” BS
275/60/15’s
1.25” spacer

And I still have a lot of room to spare

The wheels I want I have to decide between

15 x 10 with 4” BS

Or

15 x 8 with 3.75”

It seems my car is a little raised at the rear so I don’t think I’ll have a problem with rubbing on those backspacing but I would just like the gap between the top of the tire and arch to be a bit fuller , that’s why I thought maybe a 70 profile

Thanks

P.S the car is not on the Jack in the pics , I had just lowered it down