Like quite many other PEers, I experience similar problems. Stretches have been working for me quite good, I still see gains and ain’t planning to hang, since stretching is so beneficial for me, but EQ declined very noticeably. What aggravates my situation is that I quite often over-train.
Despite that, like the others in this thread recommended, I’ve been doing jelqs and kegels to offset the decline of EQ. Additionally I started pumping very moderately. And I see certain improvements. It usually takes several weeks (depends on a person, I’d say from 2 to 8 weeks) to more or less tangibly increase your EQ. So, you need be very disciplined with doing kegels, as well as with PE in general.
But note, that both jelqing and pumping increase your fatigue, so you are supposed to find a balance among all your exercises, and, presumably, significantly cut back on stretching to avoid severe over-training.
Since your are already conditioned, let me suggest you the following solution: do the same workouts of jelqing, but shed the time of your stretches by 40% and incorporate in your routine 2 sets of low pressure pumping 5-6 minutes each. Naturally, then adjust this routine depending on your fatigue and EQ. IMO, that would be a good combination for both length gains and improvement of blood circulation. Plus 7-8 minutes of 5-second kegel-contractions 6 on 1 off.