Suggestions for a Stretching only Routine

Hey guys, I’ve been somewhat active on another PE forum for the past few months and thought it would be a good idea hear some of your perspectives on my current/past routine, as it could probably use improvements.

I’ve been doing PE since the fall of 2017 and started with a modified version of the DLD routine, where I was able to gain about .3 inches in length, and around .5 of an inch of girth within the first month. I toned down the routine slightly as I started to get some negative PIs and lost a bit of the length gains.
I continued the modified routine until December and got my length back and even a little more girth. After this I took a break for around three weeks or so.

From January until now I changed my routine to the JP90 routine in order to ease my unit back into PE after the break. From this however, I again lost the .3 inches I had gained, and continued to gain in girth (nearly an inch or girth gains at this point, but length is back to square one).

I’m happy that my girth gains came pretty fast, however I’m a bit frustrated in the fact that I cannot seem to gain much in length, which was the main reason I started PE.

With that said, do you guys have any suggestions for transitioning into a length only routine? On the other forum I was recommended I looking hangers or extending devices. Do they work any better than something I can just do manually, or will they cause damage?