Basically if the player base keeps requesting premiums then they're will be no more tanks for actual lines and branches, always consider what if said tank could be a normal tech tree tank instead of a new premium.
Take the AMX 13 57 Tier 7 Light Tank, it could of easily been a tier 6 tech tree tank that could of had the 75mm gun as its top cannon, leading to the AMX 13 75 and the Bat-Chat 12 T both at tier 8 which would of been better for the tech tree and made it more aesthetically pleasing.
All I'm saying is before you make a plea to the devs about them making a new premium, just think about having it as a tech tree tank.