Selecting Political Candidates

How do we ensure that political candidates are good quality? Can we, as the electorate, assess the qualities of candidates through their public appearances alone, or should there be some sort of prior selection process?
Some political parties already utilise assessment centres but should there be a national criteria?
This interesting article, Confucian Democracy, highlights some of the issues.
Who defines what is good quality?
Who sets and assesses the candidates and how are they accountable?
Does such a system inhibit diversity of thinking within democracy?
Does it become elitist?
Wouldn't the publication of candidates CVs do the same job but allow greater diversity, limit elitism and the power of the assessor? The publishing of CVs online could be a useful adjunct to the Interactive Democracy web site.