I think you should just make it so horses can glide, flying is a little too extreme.
As for no fast travel dude, i play without fast travel, waiting, and i use a sleep mod so i can only sleep when im tired

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this script will disable fast travel. ( you also need to make is a quest script, and attatch it to a quest )
Scriptname DisableFastTravelScript
Short Once
Begin MenuMode
if once == 0
EnableFastTravel 0
set once to 1
endif
end
off the top of my head, that should work, disableing wait is done by going through the cells and unchecking "Can Wait"
so, a pegasis would be pretty cool to glide from high places, but not to fly, solving the problem with flying above cities for the most part.
~Dirox