Centering it on Ogden Avenue would pull it substantially from the southbound exit point.
However, centering it on Chicago Avenue is completely wrong, as Chicago has 0 connection to the exit. It's an exit for
Ogden Avenue, and the NB on-ramp directly connects to said road. Plus you can say that 'Racine Avenue' (which is what the SB ramp connects to), acts as the rest of the ramp from I-94/90 since it's one-way to connect to Ogden.
Thus, IMO, it's clear as day that the point should be properly centered on Ogden.