The latest version of the veteran upgrade / balance patched maps is 2.24.
It basically makes medics, cyborgs, wolverines, buggys, obelisks, slightly better (actually close to being worth their cost). It also allows units to get upgrades after killing 3x or 6x their value in other units.
The main difference between version 2.24 and other versions, is that it really focuses on making NOD more reasonable (without making it over powered). The very large majority of 'pro' players still stick with GDI, even knowing the upgrades to NOD.
One example is on normal TS, tick tanks would loose 99-100% health to one bomber pass, now they have similar armor to titans, yet act the same way vs other units like MK or GS. Cyborg Commando still misses moving targets, but not as frequently, making building a TON2 and buying a sub/CC more worth it, but not changing its damage vs buildings.
GDI is pretty much left alone, besides medic and wolverine, and the vet. upgrades.
I have a list of all the changes, and the reasons why, as well as some bugs found in the coding of the game that have also been fixed in this version that I need to finish and get posted, but for now those are the general changes.
Some players are resistant to playing the vet/balance map, but 95+% of them refuse to play NOD.
Some pro players like c0rps who does play nod still prefers the old version, but to be totally honest, if he looses 2-3 games in a row vs another pro player, he is very likely to switch to GDI and completely smash his opponent.
Something to take into consideration as well, is NOD defense and attacks both require much more timing and micro control, and the CNCNET game speed is 60 FPS now instead of the 52 FPS it used to be. That may not sound like a big difference, but if you play on a high level, it is insane. Coupled with the fact that CNCNET has reduced 'delay' for timing attacks/defense, and less lag (in most games), it really makes NOD that much harder. One small example is that rockets/bikes don't really damage moving targets unless you constanty move/re-position them and defending 2-3 disruptor attacks at the same time in high speed games can be intense.
Something else to take into consideration is that even in a game with a pro NOD player vs a pro GDI player, there may be a rather large skill gap between them, that allows the other to play NOD. c0rps for example is one of the top players, even when rusty, so he can get away with playing NOD vs the average other 'pro' players, but if someone good enough logs on he is less likely to win with his NOD and more likely to win with his GDI.
A lot of the reasons above are valid points, but at the end of the day a lot of players are simply stubborn. The same players that complain every other game about what sucks about NOD, are the same ones to complain about anyone trying to fix NOD up at all.
A lot of players have also got used to never using medics and don't think they should even be in the game, or don't like the veteran upgrades, but fact of the matter is vet upgrades were built into the game, and rendered disabled due to the game being rushed out and lack of support for patches.
When the game was first released, NOD was way overpowered, so they nerfed it down a bit to compensate, but after doing so never stuck around to actually see how things played out, which was basically NOD sucking, unless you have 5 cups of coffee, 2 energy drinks, and are a top 5 player out of hundreds.
If you guys knew how many super pro NOD players came back to CNCNET and switched to GDI it would put this post in perspective.