Just started the game and it already looks great.
It has tons of upgrades for both your personal equipment(different googles allows you to see footsteps see through wall ,weapons,kevlars,boots,gadgets)
and your personal plane/base which helps you during the missions gives you radar ,different sensors during missions,you can unlock workshops so that you can get prototype weapons,other things like revealing dead drop locatins,health boost,a perk also allows you to customize gear during missions.
So after playing about 7 hours game is still awesome campaign might not be as long as I suspected since it asked for disc 2 after about the 6 th story mission. It has plenty of sidequest as well like eliminating all targets getting intel,hacking..etc also there are ingame challenges like perform 20 non lethal takedowns,shoot out 50 lights,get 50 kills with each weapon etc which reward you with money.During each mission you can find laptops to hack,people to capture and usbs to find for extra cash.
There different type of gear like nanotech vest or kevlar which either increases your armor or stealth same with boots ,pants,gloves increase your weapon handling skills.
Also if you complete the sidequest you can get new equipment which is nice
This game has been amazing so far. Every mission has been an absolute blast. The wave mode is also awesome and gives the game a ton of replayability. Spies vs Mercs is surprisingly really fun and also adds a ton of replay value to the game. Customization is great, the variety in weapons is plenty, the gadgets are a ton of fun to mess around with. So far, I don't really have any complaints except I wish there was a mode harder than perfectionist. I'm handling it a bit too well, although it does have difficulty spikes. Besides the hardest difficulty still being a bit easy, the game is perfect.