Once you hit level 30 and complete the campaign, the only way to obtain credits is by multiplayer, and at level 30 the matchmaking becomes extremely tedious, only allowing a general gain of 3000 or so per hour because of the lack of suitable opponents. Thus I propose a campaign reset function, and perhaps an achievement for completing the campaign multiple times?

There is a way around this, which is to simply not complete the campaign and purposely lose a few AI matches, because this re-locks parts of the map, allowing for potentially infinite credit farming (you even get creds for dying, so)
I didn't realise this until actually finishing the campaign though, which is partly why I bring up this suggestion.

Wasn't there a kind of training mode after you clear the campaign?

Yes, but as these 'practise' mechs are essentially unbeatable, there's no way to continue earning credits in single player.

Strange, I remember when it was first released many players talked about how it was so much better than the campaign. Maybe they changed it since then though.

Definitely. The only issue I have is with hassling credit earnings; there's no technical errors at hand here.

what "practice" mechs are you fighting? because if they are the same ones I am fighting they are insanely easy. when I am testing a new builds I let the cpu go 2x first without me doing anything. that way if I cant catch up and beat them then it will be a decent pvp build. honestly if you are having a problem with the practice bots then just make a pure heat build and over heat them over and over and over. lock them down. cant lose

Tell me this is actually a winnable fight:

Try clearing your cache and cookies.

Thanks Korupt, clearing cookies and cache reset the AI back to feasibly fightable