Why more NOD upgrades vs GDI upgrades

Won't go into NOD vs GDI balance too much, but here is the quick and dirty: NOD barracks is more or less on par with GDI. They enjoy chem troopers where GDI gets 2 range units. NOD air is more or less on par, perhaps a slight edge to GDI for mohawks. Banshee is a great all-rounder unit, but it falls apart to mass talons, or mass pitbulls, both found in GDI, and almost every deck. Lastly, NOD war factory is MASSIVLY underpowered compared to GDI. Predator tank kills scorpion and still has enough HP to leave another scorpion left as a 1 shot for the next predator to roll in on. Pitbulls beat bikes, but as pits are raider, this is a no brainer. and lastly, even though a giga is more expensive, a stationary giga can sit and zap a moving mlrs as it gets into range, unpacks and then destroys the giga with most of it's HP remaining.

So running NOD is currently a disadvantage over GDI. of course, your mileage may vary.

That said, I main NOD and most of my crates are almost or completely GDI drops. The game tends to give a slight weighting towards your lowest cards, so if you give away all of 1 faction, you will typically gain more of that faction in crates to make up for it.