I believe you're mistaken about the gravity. Position is as Re^(iv/rt), so |acceleration| is as Rv^2/r^2 -- right? For a fixed station of floor radius r, acceleration is directly proportional to distance from the center, R, so with r=1000m, a 2m astronaut will feel 99.8% of normal gravity at their head.
Assuming 5% variation from head to toe is tolerable, a 40m radius habitat would suffice, which could be rotated at 20m/s.
There has actually been research done on how humans tolerate rotational gravity (although not long term, AFAIK.) A 30% gradient at 0.5g is reportedly "disturbing". But perhaps long term one could become acclimated, just as one does at sea.
Assuming 5% variation from head to toe is tolerable, a 40m radius habitat would suffice, which could be rotated at 20m/s.
There has actually been research done on how humans tolerate rotational gravity (although not long term, AFAIK.) A 30% gradient at 0.5g is reportedly "disturbing". But perhaps long term one could become acclimated, just as one does at sea.
http://www.artificial-gravity.com/Dissertation/2_2.htm