Remember how the US military started comparing the F-35 to the A-10? This is the same problem, instead of it being the price of the jet, it is the price of not having that dedicated CAS in the AO (And the price for the DLC).
As Tracey has mentioned the A-10 and the Neo serve perfectly as the current CAS.
The A-10 as a plane is not so powerful as it seems to be, its cannon is effective at 2.5km (Well within AA missile range) and that paired with the relatively poor mobility when compared to the Neo can be a recipe for disaster. Also the bombs promote communication with ground troops, which is always nice, the rockets on the A-10 are also quite poor due to limited ammo capacity.
The Neo acts as a counter balance to the A-10, where the Wipeout fails, it succeeds. The Neo's gun is not the best, it can take out light vehicles but no tanks, this is paired with a similar range to the A-10. The speed and acceleration is what make it good as a boom and zoom jet as it can provide great spouts of rockets (20 of each time) in a run and get the f*** out of there quickly, and finally its bombs are superior (Not many people notice this), the bombs are more powerful than the ones on the A-10, in all situations a target hit by a bomb will instant blow up if that bomb is dropped by a Neo.
From my experience of toying around with the Dev build, I am happy to say that the Wasp quite good in some respects, with it having larger focus on AA than CAS than its CSAT (And AAF) counter parts, making it ideal for the assignment of a AA jet.....However the atgms that is featured on the jet need to be disabled/stay disabled, for the same reason they were disabled on the Xian, there is no risk with using ATGMs. Similar to the usage of the Xian, people in this jet will linger outside the AO, taking potshots at enemy vehicles, in this circumstance, there is no coordination between ground troops (Lazing and calling lazes out) or risk (Going into range of AO to ground attack).
Another pointer for the Wasp not having its Atgms enabled is giving the Attack helicopters (Those with DAGRs and ATGMs) the slight powerful feel that they did, when Apex was released is was only a small amount of time before the Xian had the atgms patched out, this is because helicopters, especially the Kajman had balancing factors associated with the Atgms. Kajmans have to deal with poor maneuverability at high speeds, a poor power to weight ratio and being quite the target for AA rockets, but the ATGMs made it worth flying "the grave for two pilots".
Just to summarize, the wasp is a good addition to Arma 3, it was a long time coming for NATO to have a true AA fighter (Shooting 30mm tank busting rounds into an AA jet felt disgusting), but personally I believe that the server's meta with certain weapons on certain vehicles being disabled allows each vehicle to remain unique and become excellent when put in the right circumstances. Making the Wasp the dedicated CAS and AA jet would eliminate the enjoyment of using the slow, tank busting A-10 or the booming and zooming Neo, even the Atgms ruin the niche role that the Orca, blackfoot or Kajman play. Also, as mentioned by @Blue Eagle [+1 CREW] a 20mm cannon inst a sufficient caliber to be performing gun runs on Tigs, Main Battle tanks or other hard targets successfully.
Simply put the Wasp should remain or be an AA jet, have its atgms removed and is not sufficently armed to replace the Neo or the A-10. This also allows people who don't have the DLC to be able to still use jets, rather than being hit with a paywall on an integral part of the server, one which there are dedicated teamspeak channels to wait for a turn.