WTF is up with reviews saying that the game is "just another fps"? How many FPS games go the merc route, combining your resources from singleplayer & multiplayer to purchase weapons and upgrades? How many FPS have repeatable missions with different objectives? How many can you play at work? It's surprising how harsh some critics have been. I think the team did an awesome job and I wish them a ton of success!
The merc stuff has only limited impact on the game since it's mostly sidegrades (so once you've got favorites you don't need any more money) and there's not much of a "must earn money" feeling like in, say, Payday 2.
I don't know how many people will use the alternate objectives except out of desperation to squeeze a little more out of the game, the list of tasks never looks like it would be fun to deal with and the looooong missions aren't conducive to simply trying stuff out. Also in my case about half or more require gear that I haven't unlocked yet so I'd need to grind some money to play them.
Portability is great and all but "it's good for a portable game" is still a backhanded compliment. There's no reason except budgeting and business priorities why this can't be a game on par with any home game (except the graphics of course but those don't matter so much). We know that FPSes can be better than this because we've seen it on other systems. There are portable games that are great - full stop. Games that are all that they can be and can successfully compete with home games for your game time.
KZM is more like a Game Boy era spinoff, a game like Super Mario Land that pales in comparison to its home console brethren and is sold primarily on the premise that you can play it on the go, unlike other games like it. Many Vita games fall into that trap, inferior versions of home console games. Basically tie-ins that only sell on the brand name of the home console version and don't get the full resources of their publisher.
Compare that to how Nintendo runs the 3DS. Animal Crossing draws people away from the TV. Fire Emblem. Super Mario 3D Land is considered by some to be better than Galaxy 2 (others disagree but it's already remarkable that there's even a contest!). Mario Kart is Mario Kart. Kid Icarus wasn't mechanically sound but it doesn't show any cut corners. The ports of home console games (OOT, DKCR, Monster Hunter 3) aren't cut down and aren't inferior spinoffs.
It's not so much about the types of games you make (you can make FPSes on portables, no problem), it's about how seriously you take them. KZM feels like a second tier game, like they're reserving their A game for the PS4 game. AsCreed Liberation, CodBlops Declassified: Lower grade spinoffs.