I'm in the same boat as you, since I fly many EWR-BOS and EWR-DCA routes. However, you should still be able to make Plat with the same amount of flights since you're earning 4 segment points on that one stop r/t and possibly 6 or 8 segments if one or both legs are Y fare. That's potentialy Plat in just 12 r/t's. Base miles is a completely different story though.

As for me, I won't be going out of my way to stay loyal to CO anymore. There had been many instances where I paid a premium or took a less desirable flight just to fly on CO. Those days are over.