Make an event with the Panther F and Comet 1
The panther F could have regular APCBC and HE shells like a normal panther and the comet could use either AP, APBC or APDS, with HE of course
Both tanks would be br4 and could either come with their own squad or go into a preexisting vehicle squad
Would be cool, however, the Panther F was never implemented into action. Allied bombing had pretty much ruined German factory capability, and only one documented vehicle went into combat; this vehicle was a Panther Ausf. F/G hybrid with a normal Panther G turret on a Panther F hull. See this article from Tanks-Encyclopedia:
Imo, a more accurate and better version could be the F/G hybrid described in the above article. Though, we do have the Ho-Ri, so if accuracy isn’t a concern I’m all for the Panther F as an event vehicle.
The Comet is a 100% viable, accurate option; these did see combat with deliveries in late 1944. See this article also from Tanks-Encyclopedia:
I do agree with @Valkay , the Comet should be a TT vehicle to give some more “umph” to the British side of the tech tree.
I’d greatly appreciate the Comet being a TT vehicle for the allies the use rather than some random event reward given that your only other option in the TT is a wall of shermans and their variants.
The Panther F being an event vehicle is fine given how developed the axis vehicle TT is.