Call it Survivor, Centre Block Edition. There are currently 105 Senate Seats, distributed by Regions:
Ontario - 24 Seats; Quebec - 24 Seats; Maritimes (excluding NFLD) - 24 Seats (N.B. - 10; N.S. - 10; P.E.I - 4); Western Provinces - 24 (6 per Province); Newfoundland & Labrador - 6; Territories - 3 (one per Territory)
Suppose, at each election, the voters in each region (or Province) is able to "retire" one Senator from their own region. The ballot question might look something like this:
Which, if any, of the following sitting Senators from your region should retire from the Senate after this election?
a) Servative, Connie) (CPC) (appointed 2012)
b) Earl, Libby (Lib.) (appointed 1986)
c) Pea, Andy (NDP) (appointed 2018)
d) Green, Pardy (Grn) (appointed 2020)
e) Pendant, Indy (Ind) (appointed 2022)
m) None of the Above (Keep all sitting Senators)
*Note: There are currently no "Liberal" (all kicked out of caucus), "NDP", or "Green" Senators, of course. I'm just trying to show an unbiased example.
I would put the year of appointment on the ballot so voters can have an easy way to decide which Senator is getting "a little long in the tooth."
Any Senator who announces, before the election, their intention to "retire" (for "health", "personal" reasons, whatever) will be held to their word and removed from the ballot. This will set up a dynamic where a bad apple looking avoid personal humiliation will open their colleagues to additional risk -- a good push and pull. We could give Senators appointed less than two years a break by taking them off the ballot (to give rookies a chance to establish their worth), or just throw them out for judgment along with everyone else.
If we could only eliminate one Senator per region or Province per election, a lot of the most egregious scandal- and gaff-prone behaviors would diminish. I would go so far as to say eliminating just one at a time might be better that getting rid of them by the bunches. After all, it is way more embarrassing to be singled out as the lone "loser" out of a field than being able to blame those fickle voters. There is no doubt, when we get rid of just one person, that the voters think you are the worse. If there are two notorious Senators, either the "runner-up" will shape up over the next 4 years, or their colleagues can give a sigh of relief.
If they know that they can be voted off, Senators will have to work harder at, not just working hard at whatever it is they do in Committee, but communicate better with voters about what they are doing to earn their place in the Senate, as well. It will no longer be good enough to say you voted with your Party, or even that you showed up for votes from time to time. When the really bad apples are gone, Senators may have to take up causes just to get enough positive press to avoid the chopping block. They will have to become "the Veterans Advocate"; "the Arts Advocate"; "the Native Affairs Advocate"; "the Security Issues Specialist", etc. so that voters won't think of them as deadwood. It will give individual Senators something useful to do without directly competing with the elected House of Commons.
Party Leaders can signal displeasure with particular Senators, by kicking someone out of the Party caucus, without turning Senators into sock-puppet rubberstamps for Party policy. (Personally, I find Justin Trudeau's removal of all Liberal Senators a rather useless, and somewhat opportunistic exercise.) If a Party Leader turfs a Senator and the voters keeps that person, but votes out another Senator from the Party, it can be a way to rebuke a high-handed Party Leader.
One of the reasons the NDP prefers to abolish, while the Liberals prefer to reform the Senate is that the NDP simply doesn't have any "skin in the game" right now (there are no "Liberal" Senators, as such, but there are Liberal appointed Senators that they can count on for votes). There are no NDP Senators to upset. I'm not suggesting the calculations purely mercenary or Machiavellian, but it certainly plays a part. Vacating a bunch of seats by the "retirement" process will guarantee any incoming government the ability to appoint Senators to represent each Region/Province, which is a good thing. We probably need to take other steps to address the imbalance in the Senate.
By voting only up to one per region/province out at a time, most of the hardworking Senators will not be constantly following the voters' mood swings as the House of Commons does. Which is what you want, if the Senate is to be a place of "sober second-thought".
The "None of the Above" option needs to be there, or we will be voting perfectly competent, hard-working (future) Senators out, change for change's sake. Senators in smaller regions/provinces/territories might feel that they are at above average risk of elimination, but the counterpoint is that if they do a good job, voters are more likely to vote them confidence with "None of the Above", and a stronger vote for "None of the Above" would give these Senators a stronger hand when they make their case in Committee.
The day "None of the Above" out-polls all the names will be a good day for democracy.