Two most underplayed... Other than snipers, when was Infiltrator ever overplayed? I don't know about right now, but Light Assaults have been played PLENTY.
It would be great if my Light Assault received some love they suffered several nerfs the last updates some intentional (Jetpack noise) some unintentional (Closing of base windows). As for improvements, it has seen nothing. I will say the last update normalized the jetback noise, at least we do not get a horrendous -BOOM- any more. Infiltrators need some improvement, especially with tools, but they did get the wrath module not long ago.
flashbang nerf too. Light assaults need to get some better ambush tools. Infiltrators just need a few quality of life fixes such as better foot speed, a cloak that isnt obvious to people playing on a Apple II computer.
Don't forget the ability to deal with enemy armor without relying on stationary base assets that aren't always available.