Low gear set 904, pro’s and Con’s

I got a vague :) overall question, trying to work this out in my head how it would workout, isn't it gonna take a certain amount of mph eg.. 30-40 mph before any gearing catches up to the stall speed ? Which at that point probably at least 1/2 of the 60', more 1st will catch up slightly quicker but also have to shift a lot sooner with a wider drop ratio. Would the change have an effect on the speed it stalls at ? From what I understand lowers it. Wouldn't more stall be a better route if something is off ?