Doesn't 'mbalimbali' mean 'various'.
I'm not sure that "different Christians" means the same thing.
I reported it.
Yeah, I think "different" can be ambiguous in English. It can mean the members of the group described group are (1) different in nature from each other (≈ various), (2) different in nature from one or more contextually understood Christians, or (3) different individuals from the contextually understood Christian(s) (≈ other). I think 1 would be mbalimbali and 3 would be wengine but I'm not sure about 2.
Yes. I think in (1), you're right that something like "different (various) types of Christians" could be translated "wakristo mbalimbali".
In (2) you might have to say something like "wakristo hawo ni tofauti na [insert certain group]".