There are many challenges in the world that seem impossible (send a man to the moon, internet over the entire planet, curing cancer) but with a few years of invested time and collective effort, it becomes mainstream and widely adapted.
As I'm sure I've said before, I'm excited to see you pushing the limits and would love to see you come up with something useful. The best contribution I can make today is to point out the folly of trying to brute-force 5-style, and encourage you to approach it differently.
Personally I think the most promising way to explore 5-style would be to focus on the 4-movers plus a systematic method of setting up other cases to those, with the objective of maximising the number of cases covered. That way, you stand a better chance of achieving a reasonable move count benefit while keeping an intuitive approach to aid with learning and recall. I'm just not sure a significant enough proportion of cases could be covered with manageable effort, but it's worth a try. You could also try cancelling 4-movers into adjacent 3-cycles, e.g. solve ABCD as (ABCE)(ED).
Edit with example:
[M', U] solves IADM speffz. IADF could be solved with (IADM)(MF) where MF is [U: [M', U L' U'].
(M' U M U')(U M' U L' U' M U L U2) = M' U2 L' U' M U L U2 = [M', U2 L' U']