As a console I think it was bad. Experimental and successful, sure. It was ahead of its time with motion controls and as such by today's standards the motion controls feel very primitive and don't always work well. Looking at the console and its library as a big picture, too much shovelware and too many games shoehorned motion controls into them for no good reason. Taking a closer look at some of the system's best games reveals absolutely masterful game design - Mario Galaxy, Donkey Kong Country Returns, Mario Kart Wii, Kirby's Epic Yarn - the system at its best was absolutely crushing it.
So overall, bad system - outdated and underpowered even when it came out, and iffy motion controls - with some absolute masterpiece games on the system.
EDIT: I will also add the inclusion of the Virtual Console was also one of the system's highlights and though getting classic games digitally is very commonplace now, the original Virtual Console felt revolutionary and had a pretty good selection of games as well.