Do you even know what kata means? The "public perception" is "forms", but the literal meaning is "how one behaves". As Shoshinkan put it, it is merely the vehicle to deliver information to you and it's purpose is to change your behavior.
Kata can be merely the "stepping through" of one technique, or the "forms" which are so popularly changed on a daily basis by those that don't have a clue how they should conduct business. You don't just "learn kata", you progress through kata, and find the techniques becoming increasingly more complex and difficult to perform (in most cases). They are designed to help you develop proper body mechanics, focus, kime', and a host of other "small things" that simply can't be taught individually due to only having one lifetime in which to learn them. They teach you to change stances, do proper stances, do techniques from stances, and to remain balanced while moving... so there is a host of information involved in kata.
As for bag work, there is more to hitting than just finding the target. I've watched others at our dojo "hit the bag" and the bag swings on it's chains... when I hit it, the bag pivots... the top moves... the bottom comes up, and then it swings on it's chains... one hell of a difference in force delivery.
Clearly you have a "beginner's mind" from how you discuss kata, so before you start "deciding" what to focus your training on, try listening to what your teachers say, and follow their instructions. You'll do much better than trying to do it on your own.