Nothing wrong with your numbers and procedures mentioned above.
If "out-of-the-box" numbers, they apply much to the A-320/B-737 types.
That 80 knots if a fine figure to consider.
Operating from a typical 6 or 7,000 feet long runway.
xxx
Consider other (higher numbers) if larger airplanes and longer runways.
No too excessive numbers, just slightly higher numbers.
Certainly, RTO at 100 knots can be considered for a 737 on a 12,000 runway.
xxx
Personally, the earliest "GO" speed in the 747-200 was 120/130 knots.
That is except engine failure or fire/fire warning cases.
But for a 747, you often deal with V1 much higher than 80 knots.
I mention the 120/130 knots to be above VmcG.
A typical V1 for a classic 747 is some 145-160 knots.
This on runways anywhere between 10 and 14,000 feet long.
xxx
Then think about actual conditions, dry or slippery runways.
But again, I would recommend to input the VmcG in you decisions.
Hope we do not get into the old "Pprune V1 discussion" again...
xxx
Happy contrails