It is really just another art medium~ I reckon it is much more convenient though since you don't have to go out and shop for art supplies. It also saves a lot of paper and you don't need to find a place to store your arts~
Though, sometimes it feels difficult to get a certain stroke that you want when you are the expressive type when it comes to arts.
If you are the precise type who strives to get all the linearts and colors right, digital paintings will prove to be more convenient~
Those are my opinions, at least~ I hope it is useful for ya~
I just followed the reference and I guess there should not be that much ripple effects anyway since it suggests deep water~ I think the thing I could work on though, is the transition into the blue, sea water. Like, the farther an object is, it looks more blurry and blue-ish? :3