Requiring that Senators be approved of by at least two political parties that represent at least 2/3rds of the voters in the previous election would produce a relatively non-partisan Senate that most Canadians could support.
I agree especially if the composition used a formula to make better representation than what naturally occurs through the party process. I think it is important that all Senators become independents and that there be no caucuses meanign no government or opposition representatives officially.
If both sides of the House of Commons had to agree to the selection of senators, the Senate would automatically be dominated by non-partisan independents. In the current Parliament a supermajority requirement to select new Senators would require both the Conservatives and NDP to select compromise candidates as senators. It's hard to envision how such compromise candidates could sit in party caucuses.