Bands/Artists you'd wish had done more work?

The first one that comes to mind is Portishead. In one sense the three albums we have from Portishead are virtually perfect. So it makes a perfect trilogy. But there's always that yearning for one more. It was a suprise at the time when Third was released in 2008. But sometimes I think that's their best record and there was talk at the time that there was more new music on the way but it never happened. Now time is really ticking and nobody is getting any younger although they do tour every now and then.