Heroic Journey Achievement Tips Thread

I haven't found any similar threads, but I would like to ask for any tips and tricks when it comes to finishing the Heroic Journey achievements/trophies. These challenges can range from pretty simple (like Psylocke's and Luna's) to frustratingly difficult (like Mantis' and Cap's). Hopefully this gathers lots of tips so that players can cut down on the hours from trying to get the achievements.
Some particularly hard ones for me so far are the ones that require several KOs with a single use of the Ult + Punisher's smoke achievement.

To start, going into Conquest mode can be much faster for getting some of these done (though it might be too fast for the ones that require Ult KOs). For Peni's mine achievement, place one near the doorway of the attackers when you're defending.