how about we just let the artist do what he wants? It's not like he's being forced to make a sequel, it's what he wants to do.
he could easily make an entire new game - he's popular enough to make it profitable, and he clearly has the talent to make pretty good games.
but, unless he's going to add some brand new game mechanics that will make it completely different and better than the first game, he's just recycling for profit.