I'm not sure if this is helpful or not but here is a side by side of my brand new Oasis vs my trusty old veteran Kobo. Same library book borrowed from overdrive set to the Publisher's font. I tried to get the size and spacing settings as close to identical as well.
The brightness settings are at none, max and 50%. I turned the bluelight filter on the Kobo to off. Pictures were taken under LED office lights.
http://imgur.com/a/b622tLH
Hopefully the comparison is useful.
Edit: It seems like imgur reduced the quality of the images to such an extent as to make them useless. I'll try finding a better way of sharing the full size images when I get home from work.