Ah, yeah. Not sure what to tell you about that. People wanted more portraits, so the BTA team added in the portrait loader mod, and it's been loaded up over the years by various people without regard to artistic consistency. That said, aside from special pilots (kickstarter backers and ronin), you can customize your pilot portraits. So if you want to, you could choose to only recruit customizable pilots and change their portraits to only things that work for you.
Can't help you with mech portraits, sorry.
Sounds interesting, will have to try the mustard. If I'm feeling decadent (and have the ingredients on hand), I'll make myself a grilled cheese with pear slices and bacon on sourdough.