I have literally been in the exact same position for years now. I have had a R700 .270 for a long time. Everytime I make up my mind on what to build, I change it, or something comes up and I don't have the funds to pursue it.
My latest unique plan consists of copying the
CR-Mod 1 used by O'Neil Ops. I would utilize the remage design, and have a barrel in 7mmRM, and one is something fast, flat and light recoil like 6.5swede or .270. I say .270 because with a can and the overall weight, my hope is that it would reduce recoil to a manageable level. Long actions suck. Wish I had a short action! Really makes it difficult building a rifle that you want to shoot often.
My idea consists of a 24" 7mmRM barrel, medium palma contour, and the .270/6.5swede being a short 20" sendero/varmint contour, both threaded for suppressor. the 270/6.5swede barrel would be for whitetail and varmint hunting in Virginia where I am moving to again. the 7mag barrel for Colorado and AZ elk and mule deer hunting, or for dedicated long range shooting. Both cartidges can be mag fed using either a 3006 accurate mag or AI mag 300wm mag.
I would get the folding t4a just like the cr-mod 1. Basically it would be the same rifle, just a long long action versions.
That was my silly idea of the week anyways. I think ithas some merit. Like I said though, so difficult making a long action an affordable and friendly to shoot rifle with readily available ammo.
As for optic, the CR-Mod 1 uses a nice little 1-6x vortex... For my purposes I would be going with a something like a 3-15x variable FFP. Not ideal in every situation, but the most versatile option. With the short, compact fast and flat 270 or swede, come ups are not major concern as the max range of that design would be 300-400 yards on whitetail and coyotes. But I would retain the ability to make the adjustments when needed at long ranges with the 7mag barrel.