Hi Peru.
Trim: AH2 uses a auto-trim called 'Combat Trim' or CT. Its enabled by default, and most people never turn it off. The basic premise is its effectively sets your trim close to nuetral for the speed your currently doing. Its a pretty simple table-based algorhythm from what i understand. Its designed to free the pilot from having to constantly trim the aircraft as the speed incr/decreases when your fighting. I wont get into the mechanics behind why we have it - someone else can fill that in, there is a very valid reason. The key problem with CT is due to its simplicity. While its helpfull for most of the time, it's not as helpfull when your at the extremes of your flight envelope (in this case either really slow or really fast). So for this reason, and some just prefer to do it themselves, some people turn it off and have to manually constantly trim. Some people claim to get better slow-speed turn performance and control with manual trim, and i think you do, but it does take a lot of extra effort and another learning curve. For most people its just not worth the extra bother, depending on their 'style' etc - eg BnZ types hardly ever get into stall-fights etc. Some A/C seem to require more manual trim attention than others (109s seem to need a lot of trim attention). Some have best of both worlds, and have a button on their JS to turn it on when they need it, and manually trim other times when they feel it would hinder them. I am one of those types.
Also as you pointed out, its usefull to help pull out of extremely fast dives as well
Zoom: This is another some-do-some-dont kinda thing. If it works for you, use it. The people who dont do it, say zooming in restricts their SA and causes target fixation, and they say they're better shots with it off. I tend to use it, but only a very mild zoom - say 15% enlargement at the most, and i only use very quickly. More than being helpfull for gunnery, i find it more usefull to help see the attitude of your opponent's aircraft. I can tell with more accuracy if they're turning and where their lift-vector is pointing (eg tell where they're about to) - which is all very usefull. I dont find it limits my SA, but you have to be concious about not getting target fixated.
Lead Comp Gunsight: Only available in the Training Arena or a private arena (off line of 8 player if turned on in arena settings).
109s: Im no 109 expert, but your argument could well apply to any aircraft series. In the Late War arenas you can fly older 109s if you want, or older spitfires etc etc as well as the new ones. We have the other models for historic match ups and for the MW and EW arenas. But remember each were the best of their time for the job they were designed to do when they came out. Eg when the G2 entered service the K4 wasnt in service etc, and the G series was a step up from the F series etc. Also note just because the G6 is numerically after G2, it doesnt always mean its better in air-to-air combat. The different designations were not just to differentiate pure air-to-air combat performance levels. Some were low-alt variants, other recon variants, some intercepter variants, some ground-attack variants etc etc etc all having a different job and they were tailored for that job and got different designations accordingly. Some got different weapons packages to suit their roles etc. Yes the G6 peforms on average slightly worse than the G2 in climb, speed, and sustained turn rate but i assume they were not designed to do the same job; the G14 sits between the G2 and the K4 quite nicely - you really have to judge them on their relative merits not their designations.
As for dive-bombing - i dont know why your bombs dont explode. As for GV icon visibility issues thats a differnent issue from dive-bombing. I think its both a "feature" so that GVs stand a chance in the MA against the masses of aircraft flying all over the place, and partly due to the fact that most GVs in war time were camoflaged etc and i suspect that they were actually quite difficult to spot from 3000 yards away.
