I think you are missing a big part of Vega’s game by not using Claw off. Some of his best midrange pokes are actually in claw off.
Specifically claw off st.mp is amazing for hitchecking into EX Roll (meter use) and getting a knockdown.
You also lose out on his command grab which is his primary “close in” mixup tool.
In general Vega rewards you for being able to hitcheck standing vs crouching at both close and midrange. And the whole claw off vs claw on thing is both somewhat matchup dependent but mostly situational based on what you are trying to accomplish.
For me early game I like claw on so I can pester and poke then as I try and make an opportunity or try and make up a damage deficit I move into Claw off play. Claw on can be best for closing out rounds when you just need that 1 st.mp to kill them. All in all I think both are very important.