I know it does you absolutely no good to tell you that the eggs taste the same, store the same, and have the same nutritional value whether they are fertilized or not. It is in your mind and that is just the way it is. And don't feel bad about it. When I was young and invincible heights did not concern me at all. Now my concern with heights is not always "rational".
There are many different ways you could proceed. You really have to decide what your goals are. The only real reason for you to keep the rooster is to have fertilized eggs to hatch your own eggs. If you decide you don't want to hatch your own eggs, then get rid of the rooster.
If you do want to hatch your own eggs there are so many different ways you could go. If you don't want to eat fertilized eggs, yes, you need to isolate the rooster.
There is no way to know if one of your hens will eventually go broody. Whether you have a rooster or not has no bearing that. The Buff Orpington's have a reputation of going broody, but there is no guarantee one will. If you want to guarantee hatching eggs, you need to get an incubator.
If you do leave one or more hens with the roster in his pen to keep him company, what are you going to do with those fertilized eggs? You can only store them for so long for incubation before they start to lose fertility.
If you hatch chicks, about half will be roosters. What will you do with them?
My goals and set-up are different from yours. I cannot tell you what to do. I will tell you that with a Buff Orp rooster, the Buff Orp hens will give you Buff Orp chicks, the RIR hens will give you red chicks but probably a little lighter that that the RIR's, the Barred Rocks will give you black sex link chicks with the roosters barred and the hens mostly black but with some reddish-buff around the neck. I am not sure what the Araucanas will give you, probably some sort of Easter Egger.