In looking at your system, I don't see anything obviously wrong with it. Yes, you need to keep after a canister filter, and the tank will outgrow the tank, but that's long term. In looking at the pictures, the tank looks a bit dim, and the corners of the tank do seem very dark. I think it's safe to say the lighting improvements would help quite a bit.
The whole trick to anything on a reef system is trying to make sure any upgrades are going to be cost effective. No point in spending a lot if your not going to get a big benefit to the system. Since you plan to upgrade the tank, you might be better off spending any money on your upgrade.