The post type grip sub-assembly does not lend itself well to a lot of grip types and it completely precludes attaching a lanyard ring (not a popular option, I Know.)
Neither of these statements are correct.
Maybe you're not satisfied with the shelf-ready factory options you've seen or haven't looked much for custom or semi-custom items, but the internal stud, "hidden tang" grip of the GP100, SP101, and SRH allows for a far larger spectrum of grip profiles than the traditional style, exposed backstrap Redhawk.
It's very fair to say there are a lot of guys who are fans of "traditional" revolvers, so they favor shingle style grips over internal mount grips, but it's a lie to say the exposed strap type offer more options. How many grips have you seen for a Redhawk which didn't retain the exposed backstrap? Few to none. Which means the backstrap profile better fit your hand, lest the Redhawk can't ever fit your hand... A guy can cut a broad range of profiles for the Super Redhawk.
The second point about lanyard rings is also false. Bowen offers a lanyard ring screw for the Hogue grips in the SRH/GP100, and any machinist can replicate the same. Before I became aware of the Bowen grip screw, I made my own by D&T'ing the end of the grip tenon, then used a bushing to stand through the grip itself, between the screw head (accepted a swivel) and the end of the tenon. I made mine from a hardware store bolt, welded the head to build up enough stock, through drilled for the swivel, then turned in a drill press against a file to round the head. I had about a dollar, plus a Saturday afternoon into it. Since the Bowen part only works with Hogue stirrup type mounted grips, my method of D&T'ing the tenon directly would work with any clamshell grip. Bowen's ring screw pictured below: