I'm a bit lost with all this tbh. Not sure I fully understand what you are trying to say Dojj.

If you lift the weights you mentioned above how many reps do you get? Then when you add 5kgs, how many reps?

5 ,inutes rest is far too long btw. Those rests of a minute or two are plenty. Less if you want more cardio and fat burning properties as apposed to muscle growth.