Concerning End Game

[DamarusRex]

So I beat the game, got the credit thingy, and back to the boat. But I don't earn money anymore, there are no more missions available for me to capture new monsters (I miss a few). Basically I'd like to unlock and buy everything that is possible, but it's kinda not allowed, all I can do is new game+ apparently.
So am I missing something? Should I newgame+? In this mode will I be able to definetly buy/unlock/capture everything?

[newman]

You should do newgame+ for sure. There's even a few achievements tied to it.

[Best Fox Ever]

It is possible to capture all enemies in the first playthrough. You can sail to the previous areas after you have finished the game if you missed some of the Hidden Recruits. There are couple of guides to get all the Hidden Recruits, like this:
https://steamcommunity.com/sharedfiles/filedetails/?id=460132011

New Game+ is also a good option to start the game from the beginning. You have to finish the game 3 times to get all the Achievements (Ironed Out The Kinks):
https://steamcommunity.com/sharedfiles/filedetails/?id=510060125