OK, so your gf is “110% satisfied”, things are going fine for you penis-wise, but you’d just like a little more? I think you should be able to find something that works for you. You are probably never going to be able to follow the “add time not force/weight” adage as you get more into your routine unless you eventually decide to experiment with a stealth ADS (which is also going to depend somewhat on privacy, how much freedom you have to check on your member during the day, etc) if your GF is with you all the time.
Fully progress through the newbie routine (if you haven’t already), and don’t add too much too soon. You will at a minimum end up with a harder, veinier erection which your gf will feel. Hopefully, some newbie gains as well. If you have so little privacy that you can’t even manage time to do enough reps of the newbie routine a few days per week, I’m not sure what to tell you. I’m sort of in the same boat myself; I’d like to make a comeback, but I’m having to go stealth because of a houseful of kids and a wife who thinks I waste enough time as it is on other non-crucial activities.
If you can at least muster a minimal routine of stretching/jelqing and supplement with some form of ADS, traction wrapping, or whatever else some of our members have come up with for anti-turtleing, I think you would see some gains.
Good luck to you.
Size