The Ranch has flat ejection so as not to hit the scope with the brass, also. The standard Mini ejected more up and about half your brass would bounce off a scope mount. This usually never bothered it, but does put dings in it (and your brass).
The Ranch didn't just COME with rings, it had a different shape to the top of the cast receiver to accept those rings, also.
Because it was redesigned for better scope use, it also has a flip-down rear sight. The standard Mini does not.
For many years, both models were in the catalog (in blued and stainless) and easily available, with the Ranch costing more.
Ruger Ranch Rifles were specifically designed for mounting today's scopes or other optical sighting systems. They feature integral scope mounts on their receivers which can never shoot loose, patented Ruger scope rings at no extra charge, side ejection to clear the top mounted scope, and a patented recoil buffer, which protects the scope from damage or shifting impact when the mechanism parts move automatically during firing. The Ranch design has been around for a long time now. The newest improvement is the heavier barrels.
Also the standard mini came with an adjustable rear peep sight, had to use a bullet or a special tool to adjust it but it was adjustable. The ranches rear flip up peep sight was slightly adjustable with an ididy bitty screw driver.
I think standard minis were sold up till recent years like maybe one or two years ago.
The Ranch came out in '82---BUT was sold along side of the STANDARD model------with the retooling in 04-05-ish, All Mini's sold since have been "Ranch" models with provisions for scope mounting and mechanical ejection instead of the spring loaded plunger in the bolt face--al la AR-15.