Gravity :
Note that the same gravity doesn't mean the same size - various planets may
have various densities - so two planets of similar size may have different
G. I didn't remeber that gravity differences can be big in our universe
(maybe we have astronome or planetologist near who can illuminate us) - but
this is fantasy world (remember Hollow World :) ? )

Duatha

PS. IMO (and some of my friends, and my scale), 'main' continent is smaller
than Europe - take maps and check it ! - so where are other landmasses ?
Maybe we Northern Oceanus on Aebrynis...