Not sure if there is still new innovation that can draw the interest of players.
Perhaps there is one, but still it boils down as how it is going to attract slot players because playing them is just basic, you just have to understand how it works and what is the draw line and what characters will be the bonus for a particular game. So it's hard to reinvent the wheel for slot machines because we have seen them all.
Most players are seeking simplicity and games without too many complications and I guess that's the edge of the slot. Players are contented with it because of the basics of the game. They could make a simple innovation that could make it more exciting but changing the whole game could only make it too complex.
From the start they created a game that was simple and not too complicated to look at and play. and this is what makes them in love.
I personally like this game because of that because it's the simplest thing I've ever played.
apart from losing and winning it is a risk but fun is what keeps me here. Their visuals and their ease of play make me unable to stop playing slots
The game is having the most simple concept which i could really not deny that those things you do said were true which is actually on point.They might differ in design
and sound effects but the overall concept or game was just the same and its true that the simplicity of the game which do make it love by most people.
Changes? This would really be a hard question an something that should be answered because not all ideas would really be need to be applied first.