You could always get a capable but unskilled teenager to do the "hard" work allowing you to do the skilled stuff. That way speed will not be an issue.
Indeed - get someone who is willing to pumice stone woodwork with cold water , mid winter - and you`ll get as good a decorator as my Grandfather, died a poor man tho
God that brings back memories, Soda blocks, in the days when most kitchens and bathrooms were glossed and were washed with a soda block to kill the gloss and give a key. Two of you sent to decorate a room on a Monday morning, sheets down, two pairs of steps or trestles, baton across and two of you with 6 to 8 inch brushes getting a coat on the ceiling before 10 o'clock tea break. No rollers back then.