This sounds like a terrible idea. But what if we had a infection server with all the old maps and system back before the reset. This sounds like a bad idea but I don't know its worth a shot.
This would split the Infection community into two which would inevitably cause it's downfall and ruin Infection. The old maps would be added right now, but during a crash a few years ago some of the schematics were lost.
No Support. When the New Infection was released, there was, for a short while, an /Infection2 , which was the Old Infection server. Due to the existence of the New Infection though, there were rarely enough players for the game to even function properly. With numerous glitches and a population generally near that of Hellblock, the server was quickly removed. Since the New infection isn't so 'new' anymore this now presents the problem stated by @Scorvix , so it's still a bad idea overall. I liked the Old Infection too, but it just wouldn't work. (Besides, the new one isn't so bad anyway.) As for maps, you could make a thread suggesting that specific ones be added back in, maybe even try to make a replica of the ones that you wanted if they were lost.
Me personally being a massive og and knowing those maps it would be fun to see them again, though paying for a server just for that would be expensive for mv, a solution to this probally could be adding some back onto the regular server, I know ones like hijacked are still there because they are visable from spawn, any other ones unless somebody is willing to remake it wouldn't be able to be readded. Ima just put a neutral.