That is a hard one. I think many will reply, your happy with the mini-15 so stay with that design. I few more will say, your going to buy both so it doesn't matter. If it were me, I'd say go with the commander for a few reasons:
1) It is really the flagship design of the company with respect to the the one that put them on the map.
2) It is the one that Ernie carries himself. I own one my self.
3) You have had the CQC-15 experience, now have the commander EDC experience. Find out why it is so popular. In the "Love Group", many own all the different sizes.
From the user standpoint, Ernie owns a working Ranch. It is his EDC and it is used for everything. He has his choice and if it wasn't versatile, he would carry a CQC-8 or the CQC-10 (something that works). Based on my experience, it really covers all the bases. It is very user friendly for EDC. It can be SD, EMS (EMT), LEO, Military, Wilderness survival, WTSHTF (when the S hits the fan), and it has a cool factor. Like I stated; find out what everybody is talking about. I'm in the market for another one myself.