It's quite a fun game! The core gameplay is still what it used to be, and it's a little easier to control. I like the abundance of features to mess with, as well. The variety of things that can happen after you beat a level is fun too.
But I do have to admit that graphically, it looks like a downgrade compared to the original. Everything felt very consistently and deliberately designed in PowBall DX whereas in Renaissance, it looks very much like a phone game. The choice of font for the menus feels out of place as well.
The simplification of some things (like the removal of the money system) is understandable, as it makes the game a little more streamlined. But some elements were oversimplified, like the removal of weapons to buy in the store. Choosing what weapons to buy and how many of them was an interesting part of the original game. You might lose a cool weapon when your paddle gets destroyed and then you have to deal with it cleverly, and it also got me trying out different strategies and combinations of weapons in a level that took some time to beat, which kept it interesting.
Sorry, this kinda turned into a rant, didn't it? :P I'm just glad you're still out there making new PowBall games!