if they spawned on the beach and not further inland then i think this would be fair.
i think the CV would have to come to a complete stop just off shore for this to work. it couldn't be moving, evading or circling, it must be sitting still and the beach must be within the radar range of the CV, or the lvt spawns into the water next to the CV as usual.
one benefit would be that a CV could roll up close to a beach and immediately spawn lvt's to try for a base capture. having to get that close to shore puts the CV at great risk so its a balance in fairness. risk vs gain.
a CV could spawn an entire wave of troop carrying lvts in a coordinated strike within a short drive of a town. but it wont guarantee a free ride or easy capture. the CV would be sitting within the range of even tank main guns so if the attackers don't get and control a cap on the base the CV would be stuck sitting dead in the water, if the defenders respond quickly the CV would get sunk fast.
granted there is ample room for abuse, but its the same abuse that people currently use to capture undefended bases. those who chose to will game the game no matter what is allowed or disallowed. this new spawning ability would be no different, it would be up to the players to prevent its abuse by defending their coastal bases from a quick strike CV attack. so lets not argue the con's of this theory based upon those few who would abuse it, but instead argue the points of fun in its use derived by those that want to have a good time playing the game correctly.
good idea in my book
FLOTSOM