The Spit9 and the F6F-5 has me torn. Probably those two planes are the weakest link in my suggestion.
Essentially, my perk agenda suggestion is based upon splitting monoplistic plane usage by limiting them with a price:
1) Limit the "one-plane-do-all" aspect
2) Limit the "exclusive performance margin" aspect
3) Balance the plane set according to (albet lossely) an era
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The problem persists; despite the new suggested agenda, the Spit9 is the only plane that is on par in usage to other high-performance planes, despite the fact that it is essentially not a late war fighter, not an exceptionally high performance plane, nor a multi-purpose plane.
Literally, it's a plane that claims usage, which has nothing to do with all of the three major points of above. Literally, it's an easy plane to fly.
While a plane so simular in characteristics with the N1K2-J, the Spit9, the Spit9 lacks in spray quality.
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Also, as analyzed in how a crowd moves to other planes when one preferred plane becomes perked - naturally it can be expected that the usage of Spit9s will rise even higher with my suggested perks. In my previous analysis, I have made the conclusion that people flock to a certain plane of simular attributes - that means, naturally the N1K2 users will flock over to the Spit9s, which means the Spit9 usage will go over 12~13%.
Now, the worst case scenario is, with the new perkage, all the former F4U-1C pilots who flocked to the La-7, would also move to the Spit9. That would "regroup" the former Chog crowd into the Spit9, but due to perkage, the people who would not fly Spits, N1K2s, La7s or Chogs anyway, would be more diversified in their choices.
Thus, we would see one plane at the top, the Spit9 maybe doing about 15%, if worse 18~20%... and all other planes in equal 1~2% status.
The new 'best contendors', such as the P-47D-11, Fw190A-8, P-51B, F4U-1.. the fastest free planes on deck, may do about 4%~5%.. but I don't think that would happen.
People don't go to the 190A-8 or P-47D-11, F4U-1 just because they are the fastest planes - the 47 and the 190, F4U-1 are initially pretty hard planes to master.
So, what I estimate is this - Spit usage goes way up, since the N1K2 people would flock to the Spit9.
The La-7 crowd splits into two, a part of them forming the new "La-5FN" block, and another part of them assimilated in the Spit9 crowd.
The P-51D people move over to the P-51B block, but the lack of P-51B's multi-purpose capabilities, and lesser firepower, limit their effectiveness.
So, What I estimate is..
Spit9 16%
P-51B 7%
La-5FN 5%
F4U-1 3%
190A8 3%
P-47D-11 2%
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and all other planes, including lightly perked planes, diversely at 1~2%... and the 'beyond help', 1939~1940 planes at under 1%.
So, I guess it comes down to this.
In the worst case, how would it be, if all the La-7 and N1K2 crowd are assimilated into the 1 plane, Spit9? Would the overall frustration levels be the same?
I think, maybe not.
The Spit9, at least, hasn't got 4 cannons and 900 rounds. It's very close to the N1K2 in flight characteristics, but it has fine differences - it hasn't got the "UFO" quality. You see the N1K2 sometimes doing strange and incredible things, but you rarely see a Spit9 doing that. It doesn't dive as good as the N1K2, too.
Also, it can't just run away at a whim(with the perkage suggested, none of the planes can!). It's not the fastest free fighter. Neither does it have that incredible climb rate from 0 to 5~7k alt, nor is it a high survivability fighter which covers up for lacking pilot skills - it has always been, and always will be a low survivability fighter(note, the La-7, despite it's high overusage (over 10%) from the "dweeb" crowd, still has over 1.0 K/D).
So, for the price of seeing all the "dweebs" horded into one plane type, their overall effectiveness drops down dramatically. For the price of seeing as many Spits as all the former numbers of La-7s, N1K2s, and Spit9 gathered into a single Spit9, we achieve relative variety among all other fighters.
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That's the worst case scenario. At the very worst of the worst, the "variety" issue remains the same - but still, the jabo plane effectivity is in place, since heavy bomb fighters are perked. Of all those "dweebs" who just point nose down and run, still, they can be caught this time. Also, suicidal base porking is limited - at least it won't be that effective when they all have to carry only 500lbs and maybe two or four rockets.
So then why don't we just perk the Spit9, too..?
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That's what gets me torn. The perk agenda has a nice, rounded form thanks to the fact that it shifts certain segments of the planeset into a uniform "late '43"(maybe with the exception of the P-47D-11, which is essentially not that different from '43 P-47Cs or Ds) era - probably one of the reasons it seems so reasonable.
But what if we try to perk the Spit9 also? A 1942 plane?? At least the Chog was a late war, very rare plane with incredible multi-purpose qualities - despite the official reasons given reflects only the usage levels, people still were reasonably calm due to the fact that it was "a rare, late-war fighter anyway.. I understand that".
But if we perk the Spit9, I fear that the people, especially the RAF fans, will not tolerate that. A plane which only advantage comes from the fact that it has a balance of speed and maneuverability, a 1942 plane, has to be perked because it's a good plane? When all other planes of 1943 even, are unperked?
There's gonna be a huge ruckus, one, that we can't just calm it down with the single reason of "arena balance".
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Thus, I hope to leave the Spit9 alone.
Even in the worst case scenario, the monopoly of the single plane visible, is still better than the monopoly of three free planes, vastly less effective than the former version of it(N1K2+La7+Spit9). This monopolized plane, at least, is not the fastest nor a heavily armed "UFO".
Even at it's worst, the other reasons behind the suggested perkage - limiting sucidal jabo effectiveness, giving dedicated jabo planes their roles back, relative diversity among majority of the planes - is still valid.
Or, there still may be hopes that "lazy" people, who are now only limited to the free spits, would actually try other planes from the Spit - if they want the fastest plane to run away with, they've got various choices - P-51B is probably the most worthy consideration, but at least it has two less MGs, and can't carry huge ordnance. The La-5FN only has two ShVAKs with 50 less rounds.
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The F6F-5 is giving me the trouble that it's a free fighter with largest ordnance loadout now. Will people still neglect jabo planes, and flock to the F6F-5?
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Thus.. there might be a need to consider perks for the F6F-5 and the Spit9, too - even smaller, 2 points perhaps.. but still, it's a path I'd like to stay away from.
It'd be great if there was an opportunity to experiment these setups right now, so there can be more fine tuning..

but as it is, it stays only a possibility..