Surefour, a former OW fragger pro played this nonstop and he said it best:
To make money: play infantry with people who will revive you. That's it.
Infantry costs me ~21k to go out and I can make it back IF I have people with me and people with defibs/smokes. Often I'll go HZ with 4-5 other guys and we'll get creamed by the deathball and that's it, That's 21k gone. The kits are only worth it if you have teammates. You're not getting a 25k kit and going rambo and making it back, that shit's not happening. Outside picking on Bobs (every kill streak clip you'll see is people killing 60 yeard old Bobs with no armor/probably no guns over and over) you WILL get fucked eventually without team assistance. Whether it's them rezzing you, suppressing, flanking, or just tanking bullets so you can spot people, infantry ONLY works as a team.
Vehicles you can do whatever you want. You can fuck around and get your 10k back with like 6 or 7 kills and then it's free money and if you're not dogshit or the other team IS dogshit, that's easy money. It's not the best money, but it's money. I've had a few 100k+ kit-lifes as infantry but only with 2-4 other people I knew in my squad and it's literally the duration of the game. I probably still died 2-5 times in that kit-life, but I had people to rez me and get us safe and secure. Johnny rocket chopper can just find their APC if it's not in a building and blow it up in 6 rockets for like 15k and then jerk off until they try to drive it in zone again.
Kit prices for infantry are high investment, medium reward. Most of that kit is going to be replaced if you're doing really well. You're going to need new ammo from dead guys, probably a new vest at some point, definitely more healing, and other tacticals like smoke/batteries. So that 20k+ isn't even a onestop go. I'll fucking put 200+ AP 5.56 into every little bird that challenges us and that's that's something like 600 bucks right there and then I have to repack mags and find more ammo eventually. I was doing RPG shit but waddling everywhere and sacrificing shit like a defib and smokes is just not worth it unless you're on FoB defense and even then some naked Bob is going to be screaming for a rez even though he's naked and you still have enemies inside/outside the FoB.
The real money farm, unless the other team is competent, is probably Driver Gunner shit. You can load up a gunner humvee with 5.56 for like 6k and then slap on armor and just bully everyone unless they shoot tires or run MAWS. It APPEARS they fixed the gunner desync shit, but it's still hard as fuck to kill them even with AP when the gunner is in the lean-back position. And the ballistic glass, as my clip showed, is no fucking joke. MAAWS work great, but you're fatboying it and you need your team to mark/call it out before it shows up on you and insta gibs you.
I think vehicles should get rewards based on what they do. Farming infantry with a little bird? Outside the Hot Zone it should be dogshit exp. Inside Hot Zone? Sure, you're actually helping. Rocket Choppering infantry? Nah, that's not your job. Rocket Choppering FoB defenses/APCS/Tanks/Humvees? Kudos! That's what you're SUPPOSED to do! Give them the money. I honestly don't know what Havoc's job is right now once you get 3/4 armor unless they blow your toes off you can eat like 9 shots pretty easily. I guess it's supposed to be an-rounder for anti vehicle/infantry, but you rarely see them anywhere but FoB harassment.
Like I said, I'm a big fan of vehicles used for a purpose rather than just as a better armored/armed infantry. Why play a 21k soldier when I can be a 6k giga tank with a lazer SAW. I believe some one said the SAW itself is like 5k and the SAW humvee is like 6500. That's a fucking bargain!
I think they'll figure it out I really enjoyed watching like 9 helicopters all fighting each other, that was cool. Some dingus just hovering over us never getting rocketed because he's 20m away and 20m off the ground is super shit. Same with Battle Buses and Humvees. Watching a battle bus pull up with two gunners in a pile of team corpses to cover while rezzing them is badass. That shit is actaully cool. Humvees running recon or baiting bullets is also cool. Humvees just driving into 9 guys and killing them all instantly, driving away, waiting for rezzes, coming back and doing it again is lame.
TL

R Vehicles shouldn't be the cheapest/most powerful kit, even if you can make more money as infantry. You're only making more money as infantry if your team plays well together, and vehicles don't necessarily need that.