Well if you do consider it (which i recommend) here are some things that need changing for multiplayer and bronze.
Bronze
Overall
-AI accuracy too high (so far the AI accuracy feels like aimbot making it far too difficult to change positions or run from the wraiths/adhis.)
-Most lower tier weapons feel weak. (Right now i have an m-8 avenger as my only assault rifle i have and a Widow and because of the m-8's accuracy it's hard to kill anything thus forcing me to use only the widow. could go on about other weapons i have but that'd take long)
-AI spawn system (Because of how small the maps are i feel that in later waves there are too many AI that spawn all at once and keep spawning more. best way to fix this is spawn a smaller limit of AI and as 2 die 1-2 more spawn. [I.E max spawn limit in wave 5-7 being 10. 1 dies, 1 spawns, etc.])
-Faction pets (as i mention below, Wraiths and Adhi should only spawn in Silver and Gold do to how overwhelming they are to deal with.)
Kett:
-Too aggressive (Right now they rush you hard, also can and will swarm one player and one only)
-Wraths (These annoying animals should be in silver and gold but not in bronze. cover should and always must be use to recover and these mutts make it far easier to get killed by.)
-Too many spawn (i know it's a challenge but the majority of maps are far too small to spawn 20 or so enemies all at once. [ME3 had slightly bigger maps making that less overkill])
Outlaws:
-Adhi's (same as the wraiths, annoying and making it hard for you to recover making you too vulnerable to be revived. Spawns should be moved to Silver and Gold teir)
-Slightly too aggressive (Not as bad as the kett, but even in bronze they are still slightly too aggressive.)
Remnant:
-So far are the easiest to handle do to their movement speed and easily predictable AI strategies.
-No changes needed
I understand that multiplayer all around should provide some challenge, but Bronze is meant for new or just lower skilled players and at it's current state it feels far from that. in my experience in the campaign, i was playing on normal and man it was challenging, but even comparing a larger world sandbox to a smaller world sandbox means that even in normal in campaign i had no problem with enemies swarming me with the same amounts of AI as in waves 5-7 of multiplayer due to how much larger the map was with plenty of cover, but in bronze and multiplayer in general, the maps are far smaller and these tweaks could make Bronze feel slightly more for the lesser skilled/new players.