I concur with the 3.0 consensus. One area of focus will be footwork. check out any pro match on YouTube and focus just on the player closest to the camera and watch how much they move even when their opponent hasn't hit the ball yet. They are constantly in motion. This helps you be ready for whatever comes across the net. It's also, IMO, an overlooked aspect of the game. Incorporating that will elevate your game [and make you tired so fitness comes into play also!].
At some point, you may want to take lessons and undo the windshield wiper backhand [using the same face of the racquet for the BH as for the FH]: this limits the amount of spin you can put on the ball and your ability to get low or out of reach shots. You can do fine at 3.0 and even 3.5 but if you're serious about advancing, the sooner you address this the easier it will be.