my personal and professional opinion (and I do review many resumes of people who are either enrolled or finished the CFA), is that i would probably wouldn’t give it too much thought, but depending on how you put the rest of your CV together, I might get the distinct impression that you are a bit full of yourself. I don’t think that there is anything wrong with stating ‘Level x Candidate’… it is neither presumptuous nor self agrandizing and is merely a statement of fact.
The CFA, as opposed to say the MBA, does not publish grades so saying that you’re better in any way is ultimately not taken as being credible, which can only hurt you. And those institutions have found better ways of saying these things than what you’ve suggested (i.e. graduating with honors, Suma Cum Laude, etc.) Sure, lots of people don’t pass the exam the first time, but than again, I’m sure there are some people out there that studied for a much shorter period than you and passed anyways and can you say that?
Also, as widespread as the CFA is becoming in the industry, there are still plenty of people who neither have it nor think highly of it, so showing tact when presenting yourself is more important than showing off.