So I know you're not supposed to do HIIT every day, to avoid overtraining that is.
But what if I do a routine like this:

HIIT = 20-35 minutes
Cardio = 30-35 minutes

Day1 - HIIT
Day2 - Cardio
Day3 - HIIT
Day4 - Cardio
Day5 - HIIT
Day6 - Cardio
Day7 - And if I don't want to, rest this day

Would you say that is all too much?

You'll know soon enough if it's too much.

If you're feeling chronically fatigued - in general and muscularly;
If you're feeling chronically sore;
If you're dreading your workouts;
If you're performance is dropping;

You have become overtrained.

Personally, this would be way too much for me, but I don't know what your life is like. I have a kid, a house, a job and do other recreational activities such as high-diving and playing floor hockey. These things all affect your ability to do that much exercise.

DO this instead: at most
Day1 - HIIT
Day2 - Cardio
Day3 - HIIT
Day4 - Cardio
Day5 - HIIT
Day6 - rest
Day7 - rest
Edit: you say that x10 times fast, sounds like a rap song lyrics or somthing lol
usally cardio only 4 times a week. 5 is ok ;( id take some joint suppliments.

It depends on your fitness levels. It looks fine though, it's not excessive, your body can sustain this amount of exercise per day. One day off a week is a must though. Keep it up!