If anything that'd probably make Vanguard even stronger. Commandos are expensive at an inconvenient timing and have a pretty hefty micro tax to use. They'll hardly be the primary reason to pick the doctrine. 0CP Assault Sections would most definitely make it the go-to commander on all close range orientated maps and outshine Lend Lease more than the new glider would Commando Regiment. The popularity of Mechanized Assault and Strategic Reserves show how valuable early game assault infantry pressure into a heavy tank is.
That's a fair assessment.
Then perhaps just the other half?
Give the combined HQ/Commando glider to Commando, and put something underused but not that powerful in Vanguard?