It's always a bit dicey to seek/give paddling technique advice online since no one can see what's really going on, but I've got a minute so I'll give it a shot...
First, congratulations on developing a solid roll early in your paddling career. Having a reliable roll allows you to run harder lines, which lets you learn to read harder water and develop all of your paddling skills. The only way a great roll can impede your progress is if you let yourself go over too easily instead of learning to brace back up. Since most people take a long time to develop a bombproof roll, this rarely happens but I do know someone who got in the habit of just letting herself get knocked over and then rolling back up. Of course, once you're upside down, you are no longer in control of your boat, so don't roll unless you have to!
Next, there's absolutely nothing wrong with keeping a blade in the water as you enter a rapid and survey the scene and maybe some of us do this instinctively on our strong side. So long as you keep your weight neutral and don't really lean on your paddle (why brace if you don't need to?) then there's no problem at all. I prefer to keep the blade more vertical so I can feel the current working on the face of the paddle. Once I've decided on a course of action, then it turns into a forward stroke or some form of maneuvering stroke to spin the boat in the direction I want to go.
Anyhow, good luck with your progress. Just the fact that you're thinking about what you're doing with your paddle and body in a rapid shows me you're on the right path. Lots of folks just focus on the next wave in front of them without any awareness of what's going on with their body, boat, and blade.