I run Bossk alot but seem stuck on marksmanship gunner. Sometimes k4, tac, or engine upgrade. Sometimes all of them!

Other than mangler cannon (I get range 1 aux arc alot more than range 3 in arc), marksmanship (only seems to be worth it if you bring a gunner), and calulation (cheap build with outlaw tech and k4) is there another way to get crits??

Rec Spec Calculation K4 and outlaw tech merc co pilot (greedo to some extent)

Calulation with recon or outlaw is my least favorite way to get crits.

Isn't there any other way than the three I said in OP?

Merc Co-Pilot

My go to stategy for rolling crits is to use an auto blaster cannon or turret, can't tell you the number of time's I've had Kavil at range 1 out of arc with an auto blaster turret and rolled crit, crit, blank. Then have my opponent rule 2 evades, I realize this probably isn't very helpful, but outside of the previous post I got nothing.

I've also been running Bossk, and I've been using Mangler Cannon. I agree that it's not a great solution (I also get more range 1 shots than range 2-3 primary-arc shots), but I don't really like the EPT solutions. Mostly because I usually want my action for boost (or Daredevil, which is a lot of fun on Bossk) or don't have an action due to bumping or red maneuvers.

The conclusion I'm coming to is that it's not really worth putting a lot of effort into crit generation on Bossk. It will happen often enough naturally that his ability is still valuable, and the ways to generate more crits are all awkward. Even without extra crit generation, Bossk has a strong pilot ability and is the only YV-666 with an EPT.

I think Mangler Cannon is still a decent use of points on Bossk (and I'm still running him that way, along with engine, Daredevil, and K4), but once the wave 8 scum upgrades are available I expect there will be more attractive upgrades and I'll drop Mangler Cannon for some of those.

Apart from Merc copilot (sucks) you've listed all the crit upgrades in the OP