CVG doesn't have to be a 2 leg commute to/from SEA. The DHL carriers do direct daily flights and Delta has a morning flight to SEA and a redeye from SEA (though it may be seasonal, it ran at least over the summer). I have a good friend who does it once a month to head home and I have done it to visit family. To qualify all of that it isn't a commute I would want to tackle 3-4 times a month. If your desire is to fly as much as possible as soon as possible, sit minimal reserve time, and don't mind stacking your schedule together so that you have a solid week off and commute back; I would say it may be worth doing it. If your plan is to fly a standard line and go home once a week, I would encourage you to consider other options.

Best of luck to you,
DD