LOLHarrier scrubs
Harrier is probably the easiest "strong" weapon to use in the game. Unless you have four players using Harriers on Dagger hazard/platinum, I still don't know how some people complain about running out of ammo all the time. There's plenty of ammo to kill things, all you have to do is factor in ammo boxes on your path of destruction.
If that's true, how about you don't use the Harrier on gold... 
I never use Harrier below platinum because it's boring. Use a Valkyrie or an Argus. Hell, use an Avenger if you can talk your team into not using OP loadouts. If you're gonna call out people saying Geth Scanner is OP, then I'm gonna call bullshit on that and raise you using Harrier on gold is OP... 
I try not to use it on OP kits, and usually without AR amps on Gold (other AR weapons need the amps way more). My fave Harrier setup is on my max cooldown specced Volus Merc (so only 5% Volus weapon passive) with Drill Ammo (Amour Ammo too OP
) and no AR amp. Thus the Thermal Clip Gear is a must for maximum chilling (which is what I enjoy doing with the Volus Merc and why I enjoy him most. My other fave setup for him is Lancer with extended & stability mag + Armour Ammo + VI + Armoured compartments). For both these Volus Merc setups, Adren Mod 3 is prefered if I have plenty of them.
Other kits for Gold with no AR amps I enjoy the Harrier on are;
- no Shockwave BatSent with Explosive Ammo & Thermal Clip
- all 6 Geth Trooper with Incindiary & Thermal Clip (still super OP, lol)
- all 6 Quarian Soldier with either Disrupter/Phasic ammo & Thermal Clip (not as OP because my focus is Sabotage & headshots for mooks, with the odd odd debuff followed by Marksman on the odd boss that needs killing fast to protect the pugs... after which my load is blown and off to the nearest ammo box I go to leave my pugs earn some kills as cleanup crew
)