Here's what I have, ignoring TC since all rotations can utilize it:
F4 F4 F4 F4 B3 T1 B4 F3 = 504 X 4, 161, 270, 280, 161 = 2888 potency over 22.5 seconds, or 128~ PPS
F4 F4 F1 F4 F4 B3 T1 B4 F3 = 2888 + 324 = 3212 over 25s, or 128~ PPS
F4 F4 F1 F4 F3P B3 T1 B4 F3 = 504 X 3, 324, 432, 161 X 2, 270, 280 = 3140 over 24.5s, or 128~ PPS (situational rotation, MP/Enochian not enough to get your final F4 in)
F4 F4 F1 F4 F4 F3P B3 T1 B4 F3 = 3212 + 432 = 3644 over 27.5s, or 132.5~ PPS (situational rotation, definitely can't always do this even with the proc due to MP/Enochian concerns but can occasionally)
In a vacuum the F4 F4 F1 F4 F4 rotation is one of the most mobile and leads to the average highest PPS due to its proc chance. That said ... with how MP and Enochian work, and TC procs work ... I'd say the F4 F4 F4 F4 rotation probably wins in practice, as simple as it is. If this napkin math is correct then they're all certainly close enough in PPS to go for the more consistent one. The F4X4 rotation also has the higher likelihood of being able to use a TC proc obtained in UI instead of AF, which is a pretty huge gain when that happens - well, it's a gain either way but more of a gain to rep a T1. Any mobility requirements/TC procs that would stop you from getting F4 F4 F4 F4 off can usually just be made into an additional F1 in there to maintain the rotation at some point.
If my napkin math's correct then ... yes I predict it will be wisest to do (opener/Sharpcast rotation) > F4X4 rotation > F4X4 rotation, assuming it's viable to do in the first place time wise. F1 rotations will always have a place if you need that F3P for possible mobility, of course.
If T2 in UI becomes the norm then F4 F4 F4 F4 will be the norm except on rotations where you have nearly full MP. F4 F4 F1 F4 F4 doesn't often let you immediately use T2 or B4 after B3.
Regardless of all that, if the F4X4 rotation works, do it if we get 10,000 MP. 10,200 MP works. 10,000 MP does not.