It'd also create a very early Assault Grenadier clown car.
While I like the idea of replacing the fairly useless Assault Groups with the Infantry Doctrine buildable 250s, combining a very fast 250 with Assault Grenadiers risks creating another Cav Rifle WC51.
That absolutely should not be combined with a call-in heavy.
In that case perhaps just remove the squad and leave it at 3CPs. It's already a 250, so it's basically a call-in clown car complete with a squad ready to be given shreks.
This way if people want to turn it into an AT clown car now they'll have to build a squad as well.