I used to feel the same way about wanting a bigger scope to do load development. I found that once you use that load with your hunting scope it doesn't shoot any better than if you would have developed it with the hunting scope. The best load with the hunting scope is going to be the best load, all you gain (maybe) is shaving a few tenths off the groups size with a bigger scope. I do all my load development with the 1-4 and 1.5x6 hunting scopes on the rifle any time they are under MOA at 200 yards it is a good enough load to hunt with with many of my scopes shooting under 1/2 MOA at that distance.
There are techniques to make holding on a target easier with lower power scopes
Now if you want to evaluate a rifle and see what the best it can do, here a bigger scope come into play.
If your having problems with your vision through a scope, a trip to a good eye doctor that is a shooter and understands your problems would be worth as much as a new scope. I'm 71, had double cataract surgery, can't see even a receiver sight any more and had to change all my guns to scopes.
