Been able to field a single one more unit on a faction which has the worst blobbing capabilities of all 5, while having to play combined arms to be able to do so, is the least of my concerns to be honest. Specifically if that faction is tied to be the worst at the moment.
Right now OH has 2 problems: the eternal issue of dealing cost effectively with light vehicles during the early-mid game and the transition to dealing with vehicles with more than 800HP and +200 armor.
If the idea is to give them more to blob better, I'll continue to disagree with you. If the idea is to give them more to counter blobs, they already have the best late game map control / blob control tool in the name of bunker. They're also amazing to block flanking routes, are cheap and easy to repair. And they don't cost popcap. Here is already implemented your idea of saving popcap with a great use vs any kind of mainline infantry unit.
I'm sure someone will say that they can easily be destroyed/countered, and I proactively respond "like everything past 20 minutes in game".