MG's are a hard call for me. As much as their was a noticeable nerf on a lot of planes I was flying at the time with 1.5.1, other planes it seemed less noticeable.
Example that was noticeable, the F4F wildcat when I went after a zero. I had my guns on him till they practically were over heated.
On the opposite side, the spitfire I barely noticed anything.
Now so far, something seems different about the spitfires guns, but I'm not sure what, or if it made them better, worse or no real change. heavier .50/12.7 and up MG's however do feel much better then before, so overall, it feels like the changes to MG's are good without breaking the game.
20-23 mm cannons - These are certainly a lot better then in 1.5.1. I can live with these how they are with the lack of module destruction because while they no longer have that edge, they are at the least the right balance of high damage with decent accuracy to really pack a punch. Very noticeable edge vs purely running an MG.
large caliber guns - for larger caliber guns I've mainly worried about fighters/multi-role, so my testing was done mainly with the IID and yak-7. Accuracy of course leaves something to be desired. The improved damage does make these feel viable again against air targets, and that the IID can be a legitimate threat, not just a shiny show piece. The question mark for me is does the low accuracy with fairly high damage still a worth while trade off without the module destruction we've had since 1.2 up until 1.5.1. I'm not sure why the changes were made to module destruction or if it's a weird side effect of more accurate guns with convergence rather then just straight dispersion. That ability in lower caliber cannons made for distinct advantages vs an MG because while it had a lower accuracy and overheating could be an issue you up the chance to take a wing off. Why even just adding cannons to the spitfire made it two distinctive planes. With the larger cannons that was still more of a change as you again had the same trade off vs a smaller cannon as you would a small cannon vs a MG. But now your talking very low accuracy and maybe a couple shots before overheat, but that one shot connects it could take a wing off.
The trade off is now more worth while then currently in 1.5.1.... but I'm just not sure how good of a trade off it is vs smaller cannons or guns.
Guns vs GT's - this in conjunction with changes to GT's as a whole has definitely in my opinion helped the ground game so if I take something like the IL-2 mod out its not like banging my head on a wall. It feels close to 1.4 which to me was fun, albeit with the exception of the fortifications that are a pain and well, the new aa changes are once again malarkey. AA was perfect in 1.5.1, and in 1.4, don't need aa to be as effective as it is in 1.6 particularly with multi roles now *end somewhat off topic detour*
Aces/Destroyer/Ace(post1.9)(#of/#) - A6M1(7/1), P-36(1), BF-109b(3), Ao-192(1), beaufighter(3/1), BF-109z(2), P-12(2), A6M2(3), P-51a(4), Yak-7(2), Bf-110C-6(2), F4F(2/4), Blenheim(2), BSH-2(1), XP-50(1), BF-109f(1), LA-5(1), Spitfire I(2), P-40 M-105(3), BF-110e(1), F4U-1(1), FW-190 A-5(4), I-16e.(1), XF4F-3(1), A6M5(5), F7F(1), XF4U-1(1), Bf-109E (1), A7M (2), I-16l (1), P-38f (1), P-40 (1), Mig-3 (1)