I think 'nice' is a subjective term. I will say having a few extra features helps though.
I had a 1997 TSC1 Ski Nautique - one of the best hulls around according to many. I sold it and got a 2007 TSC3 Ski Nautique 196 with Zero Off. The wake is very similar, but I'd say my bubble butt was better. What I will say is ZO is a night and day difference for me as a skier. I was just starting to run 36MPH 22-28 off (moving up from 34MPH) and our lake has a short setup that requires turning in 100 feet before the 55s. PerfectPass Star Gazer always struggled with getting a consistent speed before 1 or 2 ball. Having the exact same pull every single time made a HUGE difference for me. I went from running 36@22 maybe 20% of the time to running 36@28 80+% percent of the time in 12 months.
As long as the boat had ZO I don't think I'd care much. I might get lucky any pick up a few more balls, but I highly doubt it would give me the 12 ball jump having a consistent pull did. If I had a lake that was more accommodating to my PP boat I would have kept it.
It's all about getting the job done. If you have an older boat at it is getting the job done correctly, I don't see any reason to upgrade. If you have an older boat that is not performing correctly then it might be a good investment for you. This goes back to the 'nice' and subjectivity thought. What does getting the job done correctly look like for you?
Good wake, open bow, accurate times in a course, easy to drive, just a pylon and an engine? All of that depends on what your goal is.
If you're not running the course just about any DD boat would be a great ski boat. The course makes a whole host of new problems appear for skiers.