English ability is one of the major criteria.
There is no single most important factor in our experience. Important factors include evidence of language skills, clarity and credibility of documentation, overall qualifications, as well as others. The eventual decision to grant such a waiver is discretionary, so even the best case is never sure to be waived. I own a house in my home country which I intend to sell after I land in Canada. I will declare it upon my landing along with other funds I intend to bring in Canada at a later stage.