This way you can easily fill up the time, til you have the next great idea, but in excess it will please neither you nor the audience. My relationship to the blues scale is pretty much conflicting. It is easy to learn an works well on many things, but it is adictive. It sounds good, it feels good and it tastes good, but it is kinda limiting in long terms. Please be always aware of that.
Music theory is pretty helpful.
In theory there is no difference between therory and practice. That is for sure, but if you don't have a certain theoretical atempt to a solo, you are limited to your initial inspiration. Music theory will make the learning curve a bit steeper. If you are able to look at a chord progression from different points of view, you will be able to figure out a greater variety of phrases or at least you will be able to figure out at least one phrase. When you are playing a solo, you are performing kinda mental striptease, so you better learn how to dance anyways.