A For Allergic

The A-10 is the last "Attack" plane accepted for service.

A-12 is the last type classified "Attack" plane designated.

The services are allergic to the A designation.

It's an honest niche, tactical bomber.

I am starting to think that nearly all of the F-35 sturm und drang comes from pasting it with an F or "fighter" designation when nearly everything about it screams A...

In the Air Force the role it's intended to fill is one that used to be served by the A-7D Corsair II.  The A-7D was supplanted by the F-16.  The F-16A was never intended to be a multi-role aircraft, it simply proved capable of the mission.  The deliberately made it very tightly packaged to prevent the addition of things that would detract from it's pure air-to-air role as a day-fighter.

F-16C really happens because the attack mission needed more substantial upgrades than could be applied to the A model.  Look hard, nearly every mod to get to the C model makes it a better bomber and not much makes it better air to air.  Even the bigger engine is to compensate for the weight increase and it doesn't recover the thrust to weight ratio of the original F-16A.  AIM-120 integration comes long after the C has been in service, so just don't go there.

In the Navy, F-35C replaces "legacy" Hornets, which were the multi-role replacement for the A-7E Corsair II.  It probably wouldn't be multi-role at all if it weren't for there being a couple of carriers that could not embark Tomcats because of weight and or size restrictions. [Edit]

Then there's the Marines.  Their F-35B replaces the AV-8B and some "legacy" Hornets.  The Jarheads are most honest about what they wanted and are getting exactly that.  The entire goat-rope centers around their plane really, but it doesn't change...

The job is to drop bombs and have decent air-to-air.  It should be noted that even the lowly SLUF carried two sidewinders.  The A-7 is not unmaneuverable, it's just got a teeny little engine so once it gets slow it stays there.

The F-35 has been the wrong designation for a long time.  In the first place, 35 was the next X not the next F.  It should be F-24 if it's going to be a fighter.  Next, since it's a fighter-like bomber rather than a true fighter, it should be A.  The next in line A is 14... (we skip 13 because superstition).

So the Air Force should have A-14A.  Marines AV-14B.  Navy A-14C.

With an A designation it suddenly doesn't seem so horrid that it can't dogfight, and when it does win air-to-are we're giddy!

If we want to be REALLY honest about the designation system...

The Marines should have the AV-14A, Air Force A-14B and Navy A-14C...  The variant suffix goes in order of design and since the Lightning II was designed as a VTOL Marine attack plane from the get go, the A model should be theirs.

Also, normally a modification in role is applied before the primary role.  For example the electronic warfare Super Hornet is an EF-18G.  Recon versions of the Crusader were RF-8's.

The reason the AV-8 isn't an VA-8 is to prevent confusion with carrier squadron designations.