Sorry things are so tough. I would probably try dosing more aggressively. When I got Bix regulated it was when I got systematic about it, and did 0.2 increases every 3rd day. It was nerve wracking, but it got him ultimately in perfect #s. The longer one stays at doses, the slower the regulation process often is. They get used to the dose, and don't get results. If you can really push it, you can get there more effectively.
Of course you have to be able to test early to mid cycle to be more aggressive with it. You don't know when they will have that breakthrough to blues & greens, so you need to test for nadirs often. I usually tried to test for a nadir on cycle 3 and 4 of each new dose, as those are the most likely breakthrough cycles. It can happen on cycle 2, but that didn't seem to be Bix's pattern, so I often skipped that one and went for sleeping instead. If you can manage it with your schedule, I would just go for it and try to get a breakthrough and be done with the dragging in higher #s all the time. Of course I can't promise anything

but that's what I would try to do.
If something like that isn't manageable, I'd probably be looking at other insulins. It might be easier to get her regulated if you have a clear protocol to follow like they have on Lantus & Lev. It's tricky to convert over though if you are at higher doses - you can't go back to 1u on a new insulin, that's just a scary thought. I'm not sure how they do switches when you are at a higher dose, but I'm sure someone in the L forums would know, if not someone here (if you are interested in considering that option).