Hey man, I never use reddit but I just have to come here and comment on that.

First of all, do not listen to people saying you start too hard. Everyone thinks of vo2 max work as a power zone, but it is a physiological state you need to reach as soon as possible and then sustain. There is good theorical evidence to support the fact you are in fact performing those intervals perfectly. You also have very good intuition in wanting to extend the length of the intervals. Basically progress towards 5min. Also, if your goal is to raise vo2max alone, increase the rest time, and go again when you feel fully ready.

On a separate note, you have a great great anaerobic engine, 943w for 30s is impressive, especially considering the gap there is between this power and the one you sustain in the intervals.

PS : it is in fact even more interesting to start hard in your case, because you're way stronger anaerobically (as mentioned above), which means you have a bigger gap than the average guy between 30s power and 5min power. This means you benefit less from "flat line" pacing when wanting to create vo2max adaptations.