You have a lot of good reasoning and thought put into your suggestion, and I am 100% for new units to an obscene degree (even came in second in last year's new unit competition, which I will bring up constantly). But I don't think this new tank would fit in well with what I think the "vibe" of FAF is.
Aurora are quite strong, and perfectly adequate for the T1 stage, not to mention their performance carries over better to T2 than other factions t1 tank once they get mobile shields and their meat shield, obsidian. They are even unique enough to have their own tactics, attacking from over water out of enemy range, and raiding engines building naval factories. Remembering to make t1 scouts to go with them, and to do the most basic micro of kiting them back (and this is coming from the anti-micro guy), is perfectly fine.
Again, I love new units. Make a mod, it would be awesome. And what war is complete without an arms race? The new small arms every week of WW2 are half the fun. Imagine some long term chromehounds esque multiplayer campaign/tournament where each faction voted every week to add a unit from a mod to their faction roster. Baller.