This is one of the worst logic I ever read. In addtion, I need to say that most people need to learn how to make an argument. Let summarize what you say:
Hypothesis
H1. Sasuke's susanoo was using Enton weapon prior to Senjutsu chakra addition
H2. Sasuke stop using enton weaponry when Senjutsu chakra came in
Conclusion
Kishi is concealing a badass Senjutsu-Enton combination jutsu that he will unveil against Madara
The flaws
Your analysis is highly flawed. Whenever there is an unknown, you have to consider two possible routes. In your conclusion, you only considered the one that fit your fanboyism. The following are possible choice for the second route:
R1. Sasuke does not know how to combine enton with Senjutsu chakra. This can be supported by the fact that Sasuke as not use Senjutsus chakra produced by himself, and therefore cannot mix it with something coming from his eyes.
R2. Enton and Senjutsu are incompatible, or maybe Enton can be nullified by Senjutsu.
Once you add these possibilities, and let Kishi decide, your theory can be complete. In fact, there could be other possibilities.