I agree with Lyta.
Some actors don't do accents, always have some of the same of vocal mannerisms all of the time ......... *and* are very good actors who play very different characters.
Yeah, that's true, but the ones that can really get away with it are big names. For example, we expect Sean Connery to always sound like Sean Connery, i.e.
same accent, and even accept him as Captain Marko Ramius in
The Hunt for Red October.
However, accents can be toned down, ...mitigated. The big stars just don't feel the need to do it, or feel their fans expect to hear the actor's natural and often heavy accent. They don't have to chameleon themselves so much for a role, because they're bigger than the role. While I very much like Claudia Black and her accent (Hell, I find her voice and accent sexy.), she's not that big a star yet. For me, I guess her SG1 character came too soon after her Farscape character and looked (visual appearance, e.g. hair length, color and style, use of skintight, black leather outfits, etc.), and sounded (heavy accent) too much like Aeryn Sun, for me. I look at Vala and see a loosened up Aeryn Sun/Vash morph. That doesn't mean that I don't like Claudia Black with long, straight black hair and in skin tight black leather outfits, because I do. It's just that I wish her character in SG1 would have been visually and aurally more differentiated from Aeryn Sun. <shrug>
And neither one of them is *anything* like Aeryn Sun.
IIRC, Farscape
did show the non-militaristic, mischeveous, playful side of Aeryn Sun, every now and then. That was a major part of Vash and Vala.