The only thing the Parker will do better than the 621 is offering you a cabin and a head. The 621 will fish circles around the Parker, but it is a hardcore fishing machine. I usually fish 2-3 people and it is almost effortless in the 621. It is built for one thing, no compromise big water fishing, and it delivers. My wife would have taken the Parker, but she absolutely loves the Ranger now she has fished from it. Mine has IPilot and Lowrance Outboard pilot, all I have to do all day is launch,retrieve and reel. Don’t underestimate the speed, I find myself much more willing to make those lung runs to get to the fish. Never thought I needed 60 mph, but I sure do now. It has an unbelievable dry ride, much better than my Grady White. It isn’t G/W quality, but it is a solid built boat.
Good luck in your search,
Gradyfish