Eh… Id argue that sub 9.7 ish most CAS has to be well within range of SPAA to do much unless they are dropping bombs relatively blind, whilst the CAS does have some room for how they do things, they ultimately will probably be forced into both range and line of sight of an SPAA.
Its not until guided weapons become the norm about 10.3+ that SPAA can usually engage truly on their own terms.
Also not all CAS should be considered equal and not all weapons should be considered equal (especialyl at all BRs)
They could do a lot of rebalancing that would result in both buffs and nerfs for CAS by applying greater finess to the SP system.
Not only could aircraft be individually tweaked if they were strong or weak, but so could their weapon systems. (we’ve seen them do this recently with KH-38MTs, but they could do with doing it far more at all BRs where appropriate) Also having quantity of weapons also have an impact on overall SP cost where appropriate. Especially at higher BRs where unguided bombs and guided bombs cost the same amount, even though they are not equal.
For example, its always annoyed me that, in the Tornado Gr1, running 8-12 unguided 1000lb would result most likely in less kills per sorties and could be considered less safe (depending on what im facing) than running 4x 1000lb GBUs, but both loadouts would cost exactly the same SP cost. There is little incentive to run the unguided (and more dangerous) loadout at a BR dominated by strong SPAA and even stronger CAS.
Another example could be running a few 1000lb bombs on the Sea Harrier FRS1e whilst also providing CAP instead of dropping 1000lb GBUs from a safe height in the Jaguar GR1A. For some reason both aircraft and loadouts would cost the same
Id also say that the base cost of aircraft should be a lot lower, if CAP was more afordable, you may see more people bringing CAP, its kinda stupid imo, that SPAA costs 70-100? A heli with A2A weapons costs about 250? and a fighter with basic A2A is about 500-550 SP and advanced weapons like ARH bump that up to about 650-700? (even IR missiles add a cost iirc, which is really really stupid)
Whilst things vary from BR to BR, at the ranges being discussed in this thread around 9.3-10.3. A fighter gun-strafing might get kills but probably wont (especially without ground belts which could cost an appropriate amount), so its hard to justify its current SP cost.
TLDR. SP costs are equal accross all aircraft and all weapon types, even though they really shouldnt be.
Its “Ground” battle because the objectives are on the ground and need ground vehicles to win. Its is exceedingly rare for CAS to solo win a match (i’ve done it once in a GSB match) and more often than not, the team with heavy CAS usually looses the objectives and thus looses the match.