You are confusing mg for ml.
Typically sust is injected E3D, E and C is twice a week, prop is EoD, and there are more but they are uncommon. There is nothing wrong with injecting anything ED just as long as you adjust the dosage accordingly. Really ED pins would keep a more stable level, but the "pain in the ass" factor out-weighs the benefits imo.
I do understand your point though, test E is NOT as potent as say prop or suspension. I wouldn't sweat it or over-think it. Many people before you have used 500mg of test E or C their first cycle and made quality gains. 750mg a week is too much for a beginner. Do like 2 cycles of 500mg (test) then start stacking. Try to make gains off of the lowest dose you possibly can!
Just try to keep in mind your 1st cycle is really for learning how to manage sides, via you Aromatase inhibitor (AI), and it also teaches you when and HOW to pct properly.
Take AAS nice and slow. Its very, very easy to start obsessing about dosage, duration, and what to stack with what. Best advice I can give is just keep researching. When your ready to move up try to stick with classic stacks. Sometimes its good to think outside the box, but sometimes its worse to go against decades and decades of research.
I hope this helped. Have fun training buddy!