It’s so much easier to list some examples of ‘cursed’ ones..
One Must Fall 2097 definitely had a lot of good stuff in the full version. 7 more robots to play as (though the Jaguar is the best bot), and was it 75% more of the tournament mode to play. I finished and enjoyed the whole campaign, so it must have been good enough.
In addition to the Apogee’s episode model, I also associate shareware with my native Finnish bedroom coder style shareware games. These were often versus-type games, and you would get more levels, weapons etc when you registered. I was certainly happy to pay a bit of pocket money for these, every now and then. Stuff money in an envelope, send it off and receive a floppy back later. Good times.