What you fail to understand is that any doctor in his right mind can easily hit and take out a wookie failauder in that one hit.
I think you mean "Any Doctor with the right build", considering they still have to hit (out of Career Melee skill, probably low Brawn) and want to be at Engaged Range with a Marauder (so they'll need decent armor, Soak, and WT of their own).
And if they miss or fail to "one shot" the Marauder... they will be murdered.
Your example is also predicated on it being a Wookiee. My groups Soak Machine was a Trandoshan, his Strain Threshold was 12*. A Gand Marauder would have a much higher Strain (starting with a Soak 7, WT 15, ST 13, Brawn 5, Will 3).
* Sure, your hypothetical madman Doctor would have dropped him, but then your Doctor is dropping most characters. Few PCs are going to get much past the low teens in Strain Threshold (not counting Force Users and Lazersworders).
And your "Just faceroll it with a specced out Doctor" does nothing to address the issue, to wit: What do you do with a drunken Marauder that doesn't also immediately flatten the rest of the party?
Or for that matter my Gand Marauder/Doctor who has 2 ranks of Resolve and a Strain of 15?
Which, I think GMs should let the marauder shine more often than not in combat and not stress out too much about challenging them.
Well, yes, that's what my GM basically started doing. Most fights were "cake walks" for the BH Soak Machine and a bit tough for the rest of us. Every so often he'd cut the BH from the group and run 2 combats simultaneously, or some other semi-contrived scenario, to really push the Soak Machine's limits without overly stressing the whole party.
Overall it "worked", but it was a bit... thin compared to our normal non-FFG SW games.