Hey, it wouldn't be right to comment on your current video quality since you're considering upgrading your camera.
But I have a studio in mind(VRBangers/VRConk) that has set the benchmark for sharpness/focus quality and color imho. I have issues with their angles, but that's for another day.
If you could match this or even come close, it'd be awesome. So do check if the VR camera you're choosing can handle focus especially. Try them out first before fixating on one cam rig cause it can get expensive.
Many studios make this mistake of checking for such issues on a flatscreen during post production and then releasing it to us. Loads of issues creep through when this is done and the experience is bad when we finally watch it on headset. Would recommend checking in headset before releasing any scene. Givin you a headsup.
Wish you the best though😊