That's a great tune, potentially. I like the changes a lot. But one should learn how to improve over major seventh chords, rather than trying to force fit the minor pentatonic scale over everything.
I know what you are saying, but I am not sure I completely agree that there is a force fit going on. As can be heard, IMO, minor scales can work well over that progression. One could improvise the changes more closely and push the major sevenths, but that is a different musical statement and vision than the one that was chosen. I am not an SRV fanatic, but that is one of my favorites. It's the the contrast between the 'jazzy' changes and the blues that make that tune work for me. Similar to what Jeff Beck has done many times, albeit Beck does it better IMO. Lot's of altered chords over straight melody and blues...like Goodbye Pork Pie Hat. Max Middleton's keyboard work gives the relatively straight guitar work another dimension. Maybe not a perfect comparison, but the the best I can come up with right now. I view it as an artistic choice rather than a limitation.