Good points by Simeon. Lounge Lizard 4 is still pretty damn good, bark wise. On the other hand, Pianoteq allows you to tinker and tweak to your heart’s content.
Here’s another thread that may help: https://forum.modartt.com/viewtopic.php?id=4867
The infamous Dave Weiser, keyboardist extraordinaire, has written a book for kids wanting to rock, now his own son is five:
https://www.theboywhowantedtorock.com