Well, as tempting as this may sound, i think it's impossible to do. The fact that EA seems to have "abandoned" Bf1942 doesn't mean that they and DICE are no longer the owners of the source code and the other content of 1942. Making a real patch that fixes bugs, improves the technology etc. would require something like a reverse engineering and decompiling of the .exe and .dll files, which is not an easy task, if even possible.
Even if this could be done, it would create another row of problems: Depending on the changes/additions made, it would possibly break mod compatibility for some or perhaps all the 1942 mods out there, and i don't think that any of the older mods which had been concluded years ago would get an update to be compatible with the new patch. Also, it would mean to create new server files, you can't make an update to the client only. In fact, a lot of the fixable bugs in 1942 can be fixed by simply using a mod. In BG42, i fixed some syntax errors, code errors etc. by either removing/changing them or replacing vehicles etc. with completely new ones. But this doesn't touch the bugs in the .exe and .dll files though.
The list of things to do is quite long, and some of the necessary fixes and additions are a pain in the ass.
From a coder's point of view it's no major problem to rework the small amount of vehicles, guns etc. in 1942, i could possibly do this in 2-3 days. But there are other things which are way more complicated and/or time consuming, like missing/faulty animation files (ske, baf and skn files plus the con files). For this you'd need someone who's experienced in animations and most of all "stupid" enough to do this annoying work for free
Also, if changes to the ingame damage system were to be made, all of the vehicle meshes would have to be re-exported with the appropriate matID changes to the COL meshes.
Improving the visual quality would require the need for better models, since the ones from 1942 are really, really bad. They lack details, most of them are either too big or too small, most of them don't even have the right dimensional proportions. As a matter of fact, all of them would have to be replaced.
Replacing textures with high quality textures sounds easier than it's done: Since we don't have the original psd files (or whatever DICE used), all of the vehicle, plane, weapons textures and so on would have to be created from scratch using the uvw mapping of the models, and as we all know a lot of the models have very bad uvw mapping or are even using tiled textures like the B-17 and most ships, which makes it even more difficult. The buildings are another problem. Most of them use a crude mix of normal mapping and tiled mapping, and the texture names for them are pain in the ass. Without importing the model into max you can't even guess what texture belongs to which building(s). Additionally, most mods use a combination of vanilla (Bf1942) textures and their own textures, so by replacing the vanilla textures you'd most likely screw up vehicles and buildings in those mods because you'd have a mix of new, high quality textures and old, low quality textures. The most annoying problem regarding textures is the ground textures for maps. What was sufficient in 2002 looks terrible nowadays. So if a way could be found to make high quality ground textures, you'd have a huge problem at hand: If mods were to use this new system, ALL of the map's surface maps would have to be repainted. This is simply insane, especially if your mod has over a hundred maps.
This is only a small portion of the problems that would occur. From my point of view, a fan-made patch should ONLY touch the game's mechanics in way that doesn't break any mod compatibility. Otherwise you'd lock out all of the excellent mods out there, and quite frankly, those mods are the only reason why Bf1942 is still alive after all those years.
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