Why was the G10 removed?
First, you must answer this:
Why was the G10 added in the first place?
ANSWER: HTC had the data for the K-4. They even modeled it in WB. Same data. So waaaaay back, when the planeset was VERY small, they added the 109K-4. The idea was that they could get 2 planes for 1 model if they just stuck a 20mm nose gun option and "called it a G-10" (instead of a K4). The G10s had lesser performance than the K4. Some varried wildy but even the best were still below the specs our K4 has. So in all but name we've always had a K-4 model. Always.
The point was that the planeset was extremely limited, and HTC wanted to give the idea of having 2 planes but really only having to do the work to model one of them.
Why was the G10 removed?
ANSWER: It was never really there to remove in the first place. Now that HTC has the time and ability to flesh out the woefully lacking planeset in many areas (and let's face it, spitfires and 109s were 2 of the worst representative planesets before they got updated), they can include specific models. These models will apply to specific timelines also, so that use in SEA and events is better facilitated. One major problem with the old 109G6 was that it had a 30mm gun, which the early 1943 models didn't have. 1/3 the total had this, but only the LATER models of this total had it. So it was extremely over-powered when setting up events pitting it against early '43 bombers and the like. For the same reason we lost the gondolas on the 109F. It wasn't representative for the time frame involved.
You can see there's a reason to choose a specific model, and not lump all features into every plane.
Why does it NOT MATTER?
ANSWER: Look at the power curves. The 109G14 closely matches the K-4 in performance up to 16k. It even out-climbs it for a low-alt band below 5k. This G14 has a 20mm hub option, a 30mm hub option, gondolas option, and WGr 21 option.
IF YOU WANT THE G10 JUST FLY THE G14!!!!!!!
(p.s. Don't say "but at 25k it's not as good!" because if you are hunting bombers at 25k the gondolas will screw you over til it FEELS like you're in a G14 anyways! Any action at that alt should only be done with a single hub 30mm gun, and viola the K-4 already has this!