[Adger Smith]

Those ratios 2-3, 3-4 are good ratios. 23% and 19% drops.
Is the driver an experienced Stick driver? Does he understand the difference he should feel? That low 19% fall back in 3-4 should keep the engine up and pulling in the curve. That is good only if that is what your combination likes. Is it a HP or TQ combination? Back in the day I made a hand written sheet and calculated my shift points and the drop back RPM. Now I do it with Excel.
I would move the shift points all over the place, in your case. find out if the engine is going over the Tq/power curve or running under it. If it is running under it it will take forever to recover on the shift and if it is going over it will feel like there is no pull or nothing after the shift. Do you have dyno sheets to work off of? Even if you do, you need to get on the track and have a test session with shift points. Before you go plan the test. Lay out a good outline of what you are going to do. It doesn't hurt to log the "expected results" in your outline. Remember to make at least 2 baseline runs. When at the track stick to the plan as you test, then digest the results after the session. Don't get lost "in the moment" when testing.
I've been with customers that think "They Find Something" and spend most of the test session "Chasing the Rabbit" and then realize they have wasted their time. If you make enough planned runs the car will show you trends and what makes it happy. OH, it is nice to have help and input from others, but only believe 100% what "you" see and hear the car doing. That help, as well as the driver, can get you off chasing rabbits. In this day and age of low cost electronics get some data aquisition and A good video with sound will help. If you can make your test runs as a single you will hear as well as see what the car is doing. If I'm at a track during time trials I always have a crew guy (biggest) request that the starter make it a single.
Good luck.