We start with the basics:
What type of shooting do you expect to do? (target, hunting, plinking, 600yd+ target, 600yd+ steel plates, etc)
What are you expectations for the scope? (hold-over points, dial for distance/windage, magnification range, etc)
If you really want to dial it in quickly, give a shoutout to Vette @ A&A Optics (site supporter.) He has walked plenty of folks into the best-fit scope for them and even steered quite a few towards scopes from other vendors when it fit the customer's needs.
I plan on target shooting. Hunting is down the road though.