For what it is worth...
I fought some duels with a Spit14 against a Spit16 with a squaddie who is about my level. Alternated with 16v16 duels for a control group. My impressions...
Duelling a 16 with a 14 is tougher than 16v16, that is for sure, you can't just get a good angle initially and keep on turning until the inevitable kill shot. But it is not guaranteed victory for the 16 guy either. 14 is not nessecarily dead meat in a scissoring fight with a 16. Although their listed climb rates at low level appear nearly identical, I think the 14 may zoom climb better. The fact that the 14's engine rotates the other way may confuse people, I dunno. The 14 should avoid duelling the 16 in its supercharger dead band, that too is for sure. So a Spit16 does tend to have an advantage in a co-alt, co-e turning duel. HOWEVER...a Spit16 beats a Tempest even worse in that situation, so this argument is abit weak for un-perking.
Spit14 can still do what Jugs, Typhs, Ponies, 109s, LA7s, Yaks, 190s and Tempests typically do fighting Spits-engage with a workable E advantage, disengage with speed when it is lost. And the Spit14 climbs and turns alot better than most of those planes listed, and it will be able to run them down AND out turn either outright or with a slight dive alot easier than any other Spit.
My verdict? The main problem with the Spit14 is that people think it needs to be like the other Spits, instead of its own beast. I think a good 109K pilot would be hell-on-wings in the Spit14. Reduce the perk price to around 5 points, same as what the LA7 needs.