An addition thats not new gear
New music.
I like the music already in the game, but the same bot/bug/squid themes over and over do get tired after a while. Think it'd be a great change of pace to drop in and hear a variety of mission music
Maybe not just front dependant, but biome as well. Imagine heavy jungle planets with Predator inspired drums rolling, or deep bass pulsing away on a volcanic bot world
Something different from the usual suggestions but would breathe new life into the same moments