Any Good Salarian Operator Build Recommendations?

Well, you'd obviously want to max Invasion, as it's the single most unique thing about the Operative. He's far more in the support category, which is fine, even though I prefer the Angaran Insurgent version of support better. This also means you'll be wanting to stick close to your team, and that's a roll of the dice no matter what you are doing if you pugging.

Invasion- 1/2/3/4b/5a/6a

Rank 4 and 5 you are free to choose which you think is better, there are no readily obvious clear choice winners, but for rank 6 Virulence is the go-ahead (imo) because -15% enemy damage is pitiful. Addendum- when combined with Tech Sabotage it theoretically should come out to -45% enemy damage. Assuming of course, it stacks additively. The drawback here is it's extremely difficult to tell if Invasion has spread, at least for me. The initial target has barely visible indicators (red sparks) and if it spreads there is no visual indicator, but I have gotten Assist scores so it must be spreading. Invasion is great against crowds and cramped quarters (like inside Firebase Zero) and against bosses.

Shield Boost- 1/2/3/4a/5a/6b

You'll want to stick with the group, and every time you hear "Shields Down" from yourself or your teammate, hit the boost (provided the sound isn't bugged and you actually hear the callouts) Faster cooldown and increased area effect should greatly help you land more boosts on party members that need it. Rank 6a seems to be more proactive and anticipating enemy burst... which seems more effort than usually worth.

Overload- 1/0/0/0/0/0

Don't bother.

Offensive Tech- 1/2/3/4a/5a/6b

Not worrying about detonating combos so feel free to ignore it if you wish. I personally go Anti-Shield because there are many enemies that have shields, the vulnerability debuff from Invasion is more than enough to help your team to nuke it to hell. Weapon Mass Reduction opens up a good deal of heavy weapon options, but if that's not an issue Elemental Tech would also be good to complement your Invasion with for your team.

Support Systems- 1/2/3/4a/5a/6a

Rank 4 Duration goes without saying, reducing the downtime bosses or enemies are not afflicted by Invasion. I prefer Support Systems for better durability, though if you are pugging a lot, Tactical Revive is good carrying the dumbass Kroguards around. Shield Reset is also what I get, though if you get Sabotage from Invasion, and combine it with Tech Sabotage in this tree, it could be a good investment to nearly halve the damage done enemies do and then get it further reduced by whatever damage resistance your squad has.

TL;DR He's a support/debuff class, and you aren't going to be the hero Human Vanguard getting all the points, but he's solid.

Sure thing!

Currently it's my favourite.
Only Level 13 so far.

Prefer Sniper Rifles

Invasion: 1234a5b6b
Outbreak Epidemic Virolence
I don't need to debuf Enemies Damage output. I prefer Cover.
Want to effect a lot of enemies because of its staggering effect. They even stand up from cover. The explosion is also nice.

Overload: 1234a so far.
I will proceed with additional targets with 5 and 6.
Damage is crap, but crowed control is nice. Always charge it before releasing it.
Seems to be there is no gap due to number of targets to detonate.

Shield Boost: still 1
Don't know, did not use is that much.
So I think I'll go with the passives.

Passives focus on duration, weapons damage and health / shield

Any opinions?

btw ... kinda off topic:

is Invasion the new Dark Channel? (I mean a pale version compared for sure but still?)

I can tell you what I play:

Invasion: Max out for debuff. (I use this to whittle down large targets or armored targets)

Now someone above mentioned it debuffed "enemies damage OUTPUT". Can someone confirm this. The description says "Enemy Defense Debuff: 35%". That to me means you weaken their defenses (armor, sheilds, etc.) by 35%. Not their damage output.

Shield Boost:

1/1/1/4(restoration)/5(Shield Burst)/6(Overcharge) - Not going to say this is optimal yet, need to try it on higher difficulties

Overload:

1/1/1/4(recharge)/5(anti-shield)/6(EMP) - Mainly for spamming to take down shields and set off combos.

Offensive Tech:

1/1/1/4(combo)/5(shields)/6(elemental tech)

Support Systems:

1/1/1

That's as high as I have it.

Weapons: Thonkin X with AR barrel X and AR mag X
Equalizer X with Pistol Barrel X and Mag X

Equipment: Juggernaut Shield I

Boosters: Cryo or Incendiary Ammo
Usually a power amp or AR amp

I typically stay near teammates, strip shields, and debuff larger enemies and set off combos. Spam shield boost to keep them alive.

But again, I need more time with him to optimize his loadout/powers. This is what I've been fiddling with lately.

Yes. I agree.  I was speaking of the original Invasion 25% Enemy Defense debuff and then additional +10% enemy defense debuff with Weaken.

That would seem to be effective against armor and other hardened targets (35% debuff).

Did you notice the Invasion jumping to others reliably.

It seems hokey to me ATM.  They were all mooks, not bosses.

Does the Invasion need to kill them to jump enemies?

Or does the enemy just need to die and the next guy be in range (and the duration hasn't expired yet either of course)?

They fucked up Overload with the Chains not Detonating Combos, they probably fucked up Invasion too with it not transferring like it's supposed to.

Wait?! Seriously? Overload extra chains don't detonate? Obviously you have tested this somewhat (being the SO and all ..)