Part of the fun of any game is discovering new things and this game has a lot that is hidden away
It's not that Grindy, theres no other things to do in those timeslots and you gain most stats from going into Elsewhere to fight mobs anyway.
I'm not one for grinding endlessly myself so.
One thing I am not sure about Elsewhere is whether the monsters level with you , in which case you just find yourself fighting harder opponents if you only use Elsewhere to increase stats . Which is why I like getting some STR outside of Elsewhere to help .
Books give the best return for your time and you can always read them in the evening when you can't access Elsewhere if you don't need the cash from working in the Crowley
Personally I don't find this game grindy at all , if I run into problems in Elsewhere its usually my bad play .