I like both.
Some of the greatest combat sport athletes in history have fought in a ring, from John L. Sullivan to Jack Johnson to Sugar Ray Robinson to Mike Tyson to Rickson Gracie to Fedor Emelianenko. All of them and countless other amazing fighters have fought in a ring.
I don't like how easy it is to fall through the ropes and onto a cement floor, though (Bernard Hopkins, anyone?).
The cage stops that (usually--I seem to remember two fighters accidentally pushing through the cage door...). However, the cage does allow wall and stall and a whole host of techniques and strategies that simply wouldn't exist without it.
Bottom line: I'm fine with both.