.... and the situation in the Alpha Quadrant more in general? (assuming 24th century here).
I'll give it a shot.
The Klingon depiction of the Federation: Generally reliable when in an alliance with them, but prone to hedonism, which weakens them. It's a wonder they got as powerful as they did, however, they can get quite fierce when in a tight spot - perhaps that explains it. However the moment the crisis has passed they return to their softened selves, preventing them from reaping the full glory (and spoils) of victory.
Romulan: A dangerous, unreliable species. Unpredictable. They have neither honour nor a strict moral code they live up to. That is, they do seem to have some kind of moral code, but they reason around it, making what is wrong in one situation, right in another according to their perverted ethics. This vile, insipid weakness will ultimately be their downfall. But meanwhile they still maintain technological parity with us. Since they are so unpredictable, we need to monitor them very closely.
Cardassian: They are ambivalent in their approach to power. While they do seem to appreciate the coarser aspects of it - they build formidable ships and you'd better know what you are doing when you are confronting a Federation foe head on - they still seem quite reluctant in using it, they don't seem to revel in it like the Klingons do. Appreciation for the finer aspects of power is even entirely absent, which greatly hinders their influence in this quadrant, which is however still superior to ours. They seem quite gullible - they call it 'negotiating in good faith' or something like that - and we are bound to profit from that sooner or later.
Ferengi: Potentially a huge market. These people are given to hedonism, and fortunes are to be made. What spoils everything though, is their nosy attitude and their rigid moral codes. They seem to believe they are destined to tell other species -including us- how to live. But greed is eternal and it is only a matter of time before our values triumph over theirs.
Borg: A quaint little society. Extremely inefficient and archaic, yet until now they have resisted all our attempts to liberate them from their imperfections and limitations. We must gather more intelligence in their territory to understand the nature of their resistance ....
Great post. But what about the different species of the Dominion?