Like you, I did stuff at home a few times a week, to wake it up. Wall slide, door stretch, external rotations, etc. Those band resisted arm circles, starting with and trying to maintain scap position and then build ROM.
And stuff before upper body days at the gym 3-6 sets of little stuff before lifting. I did lots of bad resisted “serratus pushes” with a miniband around my back, similar to the pushup you’re into. Also scare crows,cuban rotations, etc.
As I improved my shoulders stopped impinging during day to day stuff and I really got after rebuilding my shoulders and pressing exercises. It was working so I did more. I’d do a move for the serratus, or scap tilt, then a shoulder or back exercises.
Like
Isometric External Rotation Drill x 3
Rear Delt Raise x 12
for 3-4 sets
Scarecrow x 8
Side Delt Raise x 12
for 3-4 sets
Lower Trap raise x 6
Single Arm Seated Press Machine (starting with like no weight or 5 pounds) x 8
for 3 -4 sets
Or
John Meadows Lat Activation Drill x 3 squeezes
Single Arm Pulldown x 12
Y-Raise x 10
Chest Supported Rows x 12
Here’s way more details
Here’s an article that talks about building shoulders with small isolation exercises.