I'm looking for the best word that means "being able to reach goals indirectly, perhaps, but not necessarily, with cheating or deception".
(basically I'm trying to find the best translation for the russian word "хитрый")
I think that without context that word should have a neutral meaning. But depending on a context it can appear as a good or a bad quality.
"Being a [xxx] person he was able to calm his boss down and stop the approaching conflict in the team" - an example when it serves as a good quality.
"Being a [xxx] person she was able to make her fiancé forgive her and even buy her that diamond necklace she wanted, although he had to spend all his savings on it" - an example when it serves as a bad quality.
"The [xxx] fox flattered the crow, and got crow's cheese" (a summary of the Ivan Krylov's fable "The Fox and the Crow") - another example where it serves as not a good (at least for the crow :) quality