Those bent tools like you have in your picture are IMO terrible for fixing ball marks correctly and encourage the "pop-up" thing that most people do. The tines are way too close together for me. The Pitch-Fix tool is very nice for a good fast repair. I also repair a lot of improperly "repaired" marks.
Thanks for mentioning this issue.
Whitemarsh Valley CC outside of Philly. George Thomas design, 1908. PGA Tour event from 1963-80. Every great player from Harry Vardon to Jack Nicklaus has played in competition there. Twenty years ago I would have given it no more than a 3. It was neglected, had shrinking greens, bad bunkering and way too many trees that were planted 50-60 years ago. But an ongoing reclamation project over the last ten years has lifted it to a 7, some would argue 7.5. The Philly area has a lot of great golf courses and Whitemarsh is back to being one of them. Right around the corner is Philadelphia Cricket Club, whose Wissahickon course is a solid 8, but Whitemarsh is very close on the scale, IMO, and much more accessible.
I'm no pro by any stretch of the imagination, but, you description, sounds like you are going about things quite well and have a good game plan.
While proper fitting (for you) equipment can make a difference, IMO... Good technique is more important.