Aircraft should not be receiving lower BR in ground RB based on the ordinances the aircraft carries. Aircraft should only be able to get a higher BR in ground if their ordinances allow them to freely destroy enemy vehicles without having to engage SPAA. A good example of where allowing aircraft a lower BR based on ordinances is the Mig-21bis being at 10.3 ground, while being 11.3 in air RB. This is an unfair advantage when you have to fight against a Mig 21bis in a 9.3 aircraft. If this is the case, then why is the F-14A also not 10.3 in ground BR. It only has access to unguided weapons, just like the Mig 21bis. As you can see that balance of the game is quickly ruined by allowing great fighters to have lower BR, because they do not carry guided weapons. We should not forget that air dominance fights still happen in ground RB, and those fighters are still extremely capable in those roles.
An example of a great reason to have increased BRs for aircraft in ground battles is the Q-5L. The Q-5L receives laser guided ordinances which can quickly over power spaa at 9.3 BR, so the Q-5L was raised to 10.3 in ground battles. This is benefits ground battles by not allowing such powerful ordinances at much too low of a BR.
I believe a standard needs to be set where x ordinance can only be use at x BR or higher. An example of why this needs to happen is the A-4N Ayit having access to AGM-65A Mavrick missiles at 9.7 in ground battles, while planes like the A-10 and A-7D were pushed up to 10.3 in ground battles (before the recent air BR decompression). As you can see the balance of these aircraft because of their ordinance makes no sense. So please make a standard for ordinances having to be at X BR or higher and balance ground BR for aircraft by that standard.
The current implementation of the ground BR difference for aircraft is a sloppy mess at best.