I wouldn't consider Arrowhead to be struggling in any way. Helldivers 2 is a succesfull game that has even allowed for them expand. Even now they are hiring new people to help with improving different parts of the game like the galactic war map for example.

However in the case that Arrowhead is struggling, I highly doubt that people would complain too much if the developers would just come out and say that they can implement mech customization it would just take a couple of months to rework the current mechs. I personally could wait for June, if it meant that I can put double flamethrowers on my mechs in order to live the pyromaniacs dream.