I'll give you some advice, if E-4 requires anyway near the amount of development of C41, 1:100/1 hour is not enough.

Correct development of box speed for C41 in 1+50, was 40c, 2 hours and 20 minutes - I shit you not - With agitation - without agitation, you get edge adjacency affects, and on 35mm stripes across between the sprocket holes.

But you can use 1+50 for reversal, 1+25 you can not as it forms dye and thus you will get dark/black slides, I've used 1+25 and processed it as a colour negative by colour developing through the silver negative mask instead of the positive.