Simple fix, whenever you enter an essential node always default to the highest level character (like you do in Team Up battles). I would also prefer if it automatically brought all applicable choices to the first few slots.
Example: Iron Man essential node in Ultron
Make first choice my 270 5/5/3 HB, second 70 1/4/0 HB, third 166 5/4/4 IM40, fourth 153 5/5/2 IM40, fifth 50 5/5/3 IM35. It is a complete pain in the ass to search through the roster, especially when the characters are buffed and not their regular levels.
Last PvE it kept defaulting to the wrong Starlord and the one with IM40 had a similar problems. OBW and 4hor seem to default to the maxed ones, I’m not really sure what’s causing this.