LED diodes as both diode and load for boost converter
Your suggestion could work. I have done this with a single white LED where space and cost and simplicity were paramount. The boost diode wastes voltage and hence power. Your 33V string has about ten times the voltage that I had on yesteryears' birdsnest. The prospective power savings will not be great in percentage terms. You will waste more power in the LEDs because the current is very lumpy. The Ohmic losses in the LED bulk resistance will raise the LED junction temp. DC runs the LEDs coolest. Carefully look at what you are doing. The downside may be more than the upside making the design worse off.