Any of the Custom Cruisers from '80-'90 are probably one of the best Oldsmobile designs for me, right next to the Delta 88 models of that same period.
I think its ugly because the whole front is low down, it needs to be higher up. The proportions just seem wrong
The Melkus RS1000. These actually have quite an interesting history, as they were built in Soviet-occupied East Germany. Regardless of all that, I still say that the RS1000 is one of the best-looking cars ever made. I particularly like it in this color. Also, it used a modified two stroke inline three from the Wartburg, and as such, it sounds like someone whacking an empty soup can with a wooden spoon.