The genius of Necromunda was a clean slate, compared to
40K (or Mordheim, too). Six identical House Gangs with varied Skills. Even then, some would argue some gangs were better than others. Outlanders added much more varied gangs, with varied success. Balance was a issue. What they try to do with
SW:A is impossible to finely balance. To many wildly different factions, with a "one box" restriction that is not fine tuned for this game.
If I was a bet'n man, I'd wager 20 Orks is gonna beat most any team. And, will be the most resilient team over the course of a campaign.