Nice that you have easy access to plumbing and space. A few suggestions...
If you are only using the float valve w/o an ASOV, then you are continuously running waster water so you're water is not actually off. Lastly, if you are only using the float to control on/off, you are not using your RODI to it's best efficiency. They work best when they run continuously and not on/off. With the float valve, you're turning the water on for a few minutes each time at best. If you want to control auto on/off, you can do it with a high and low sensor. Also no need to heat rodi. You can throw that into your SW mixing bucket instead. Coming along!