Let's do a bit of theory-crafting and work this out.
With a Veers lead, all troopers have +20 speed, 30% offence, plus 10% TM whenever they are buffed, plus 15% crit chance when Veers is alive. Additionally, on defeating an enemy, they all gain offence up for 2 turns, 50% TM (increased to 60% thanks to the 10% received from being buffed with offence up), and recover 10% protection.
With DeathTrooper, they all gain 10% health steal.
With MagmaTrooper, they all gain 30% tenacity (which, if the troopers gain their own trooper-ally buffs, puts his BASE tenacity to 93%). He also personally gains 70% (!) TM whenever he resists a buff, which is going to be most of the time.
With Shoretrooper, they all gain 10% max health. Additionally, when Shore taunts, he gains 20% TM for getting taunt and crit-immunity. All allies also gain 10% TM, for getting crit-immunity. If anyone uses a special while he is taunting, they gain 15% TM and he gets a 10% heal.
With Snowtrooper, they all gain 20% crit damage. Plus, whenever an enemy is defeated, Snowtrooper gains 30% TM, while all allies gain 15% TM. That means that, when an enemy is defeated, all allies gain 75% TM (!).
With Stormtrooper, they all gain 30% defence. This means that, with his new passive, Stormtrooper gains 190% defence. When he taunts, all allies gain defence up (plus 10% TM from Veers), and then all enemies lose 10% TM whenever Stormtrooper gets hit.
If I had to guess, the ideal team would be Veers, DT, MT, Shore, ST. With this the tactic would be to simply go far more often than the other guys. You would want to always have either Shore or Stormtrooper taunting, but usually both. Stormtrooper discourages AOE, while Shore hands out TM and gets healed by his passive, making killing either a struggle. You use Veers and DT's damage to take down one enemy, then use the huge TM advantage to land deathmark on the next important target and take them down.
Any time the enemy try to land AOE debuffs on you, Magmatrooper gets a go. This, along with Stormtrooper taunt, constantly knocks down the enemy TM bars while you kill whoever you need to kill.
In terms of mods, I would actually suggest almost entirely tenacity. This team would lose all its power if a Maul landed daze on enough people, or if they got stunned or shocked. Speed secondaries would obviously be great (as always), but these guys don't really need a whole lot of anything else. Crit could help, and maybe some potency here or there, but tenacity seems vital.
Snowtrooper works exceptionally well with the team from the looks of things, but everyone else is so utterly vital that he doesn't have a spot. You need Shore to protect Veers from super-fast burst (like Wiggs), you need Magma for the tenacity and TM removal, you need DT for deathmark and dispel, and you need Stormtrooper for how hard he can extend the TM lead, and for his contributions towards making the team tanky as hell.
I don't think this team would be physically capable of killing a Barriss team unless that team had one exceptionally squishy person to take out first (enabling deathmark). As odd as it may be, this team would likely be most effective against Empire and Sith teams, as they tend to use the most debuffs, which allows Magmatrooper to create a huge TM lead.
Now that I've written it all down, this team could actually have potential in Rancor. Hmm...
If anyone's managed to make it down here, first off, well done. Secondly, any comments or criticisms would be helpful, since I plan on building these guys and want to make them as good as I can.
