Picture didn't work but your link to the image did. We're pretty much on the same page. I think keeping Mcmillan a one way is a waste since if it no longer connects to Pembina it won't see a lot of traffic volume, which is why I'd restore it to a 2 way and connect it to the Scott/Corydon intersection in the east. I'd also forgo the slip lanes you've drawn in since we're trying to make an urban space.
One thing you've done a lot better than I, though, is your handling of southbound Osborne to Pembina traffic. I take it you have that traffic turning left from the right hand lane? That's a damn good idea, since drivers here are stupid and would inevitably turn right off Osborne into the left-most westbound turning lane of Corydon and block the other westbound lanes.
The kind of move you make is common on grand European avenues. Nobody turns left from the left lane, but pulls off the main through streets onto a mini service road, then make their left from there. It stops people from queueing up in the middle of traffic to turn left. It's similar in concept to the Jersey Left (
https://en.wikipedia.org/wiki/Jughandle) but a lot more elegant and appropriate for a city. I'd even consider modelling the turn lane after one of those, placing a "median" of sorts between the turning lane and traffic lanes.
Here's another map
https://drive.google.com/open?id=1zqbPjFa2sP_eZQTwKkog_4fKzqc&usp=sharing
This is fun!