Use crew cards at what level?

[Medina_Rico]

I'm at level 41 and already got the characters I wanted long ago. But I read there's some thresholds that are good for unlocking characters that will have more Masteries unlocked.

[Arzt]

Doesn't matter use them as you get them to try the characters.
You use them before you will get mastery points from them lvling for your main, you use them later they will have more unlocked nodes in the skill tree.
Anyway the points you get is insignificant when in late game you are getting 2k points in just a couple of missions

[BB Mouse]

I got my first card and picked a random char to try to see his moves... I saved the game before trying and wanted to see all of them. The stupid autosave ruined it when I'd done trying that char and loaded the game that char was still there. I am not gonna try new crewman before end game or my existing chars reach level max.

[k4t]

Would not worry about to much, You mastery points and levels quick enough post game that its hardly an issue. I would avoid recruitment till/if you plan on using them just because there is no reason let the auto progression go to waste even if minor in the grand scheme of things.

[brunolm]

My crewmates are capped on 45, how do you get them to 60? I already unlocked Proud...

[Label07]

I really don't like how crew recruiting was done in this game. They can either be super low level when you obtain them or max lvl60. Progressing character levels is super tedious (unless you spam Airship).

I tested waiting till lvl100 with ALL my current characters (starters) then obtaining new crew, they cap at 60 which was a letdown, I was hoping for them to come in at 100 since I already put in the time to get the starters to 100.

That said, I would say it's smartest once they are available to obtain as lvl60s GET THEM. They will level in the background a bit while your main party/character does quests/missions. In my case I had all the quests complete minus repeatables so back to Airship I guess, sigh.

[Cyiel]

I unlock them as fast i could and by the end of the chapter 0 they were all level 60~70 without doing anything so i wouldn't say waiting is a smart move.

[ele]

Whenever you want. Getting XP is so easy later on it doesn't matter.