All of those can blank out against 4 hits and keep half their HP, so they are no gonna pop either. Stars Vipers are 5 hp ships, fangs have still 4 hp. Their only defensive disadvantage is Palpatine, while they other advantages over Fel with AC, SD and Palp in defense and offense.Dice can fail and that used to be a core mechanic. Any of the above can just blank out once and go pop. Soontir, with AT, Palp and his Token stack will negate a minimum of 3 damage on any possible dice roll. If you only have one attack at a turtled up Soontir there's no point in making it because it's mathematically impossible to hurt him.Fen Rau can get 4 evade dice, Focus, Focus, Focus + Evade Results from his title against multiple attacks. With PS9 and without the need to stress himself and behind 1 HP more.What Fen Rau does not get is Palpatine, but at the same time can Manaroo help him with target lock on top of her focus token, which makes him hit way harder than Soontir.Old Teroch can have focus, focus + Evade Results + the ability to remove Fels token stack completely and that is at PS9, personally I think the old Clone is better off at PS 7 with Mindlink or even Fearless.And Guri … well Guri can be a case of flying directly into a swarm and getting Focus, Focus, Focus, Focus, Focus and weather a complete firestorm nearly unharmed. Having 4/1 HP helps here a lot too.
Palpatine is an enormous advantage in cancelling vulnerability to bad dice. If you play long enough (like in a big tournament) sooner or later you will roll badly. When that happens with a Fang or Guri you have likely lost the game (by taking a bunch of damage or a nasty crit). Soontir just shrugs and carries on as normal. It's also not only Palpatine, but access to Focus and Evade action, which bith Fangs and Guri lack.