Well I know various people who push the Big Daddy well into high power but that's not me. But yes I intend for the BT-80 and BT-101 sizes to go slightly into MPR.
I do intend to mean well here, but this last line is making my spider sense tingle.
My apologies if you are experienced in ALL of the following:
building mid-power
flying mid-power
SUCCESSFULLY RECOVERING midpower.
if so, build away and ignore the rest of this (or just ignore the rest regardless, unasked for advice is usually ignored anyway.)
First, "mid-power" itself isn't an official level, and no certification exists nor is required for E, F, and G motors (well, I think maybe there are some G motors that may be technically high power, but I digress.)
Second, just from you initial question I suspect (again perhaps wrongly) that you do no have a whole lot of experience with LOW POWER. A logical and I believe likely successful pathway is to build, fly, and successfully recover a number of low power kit rockets first. At that point you can either move into mid-power kits, or scratch design some LOW power builds. In any case, while your enthusiasm is wonderful, I'd recommend at least building some mid-power kits before scratch building mid-power rockets.
I'd also like to know more about your flying field. I believe that ALL rockets should be launched with a "reasonable" probability of recovery WITHIN a safe recovery field. I cringe every time I read about somebody saying they are going to put in a Z motor and "yeah, I know I probably won't get it back, but......"
From Trip Barber's Safety Lecture 2020. Attached is the PDF. Good read with good pics.
"Both parachute recoveries and ballistic trajectories can land farther away than vertical-flight apogee altitude. It is unacceptable for these to occur outside the boundaries of the launch site."
Nearly 75% of failures were recovery issues. Bigger rockets don't always go to higher altitudes, but often the temptation is to fly them higher. And bigger rockets are more likely to have unpleasant consequences if they land in unintended areas. start small and work your way up.