The argument against this is that generally speaking, US presidential elections are considered the most important, so turnout on any election on “off” years, or even “off” days, is considered a sure way to get less voter turnout. Is this not a pattern observed in Canadian elections?

I'm not sure I follow. Assuming I have this right, there are no "off year" elections in a parliamentary system like in Canada. Elections occur when the government in power receives a vote of no confidence. In a minority government situation this could be the first session after an election. In the rare occasion that a government makes its 5 year term limit, the PM will "drop the writ" at a strategic point to queue up an election.

Municipal elections do occur on a schedule here, but I don't think that's relevant since it's hyper local.

American elections for president are every 4 years, as are most other offices.

Pretty much without fail, any election that isn't a presidential one has lower turnout if not also scheduled with the presidential one, since many Americans will only show up for the presidential elections. Which is why the ballots tend to be long.

Granted, I don't think this makes them very complicated; my ballot had plenty of offices this year, and it was essentially a one-page double sided bubble sheet, with accompanying voter guides sent in the mail. It's not very hard.

And regardless, all elections are run by a non-partisan agency. Just like the health service, the police service, the fire service, and the garbage service.

Non-partisan? I mean, they are controlled by the elected government, who appoint people to do what they want. With the exception of elected sheriff's in the US, I wouldn't say it's less partisan. Take a look at what's going on in Alberta with the new Conservative gov't. Plenty of "non-partisan" government agencies are raising hell over the new policy direction.

Why do you keep bringing this up? Do you mean that these services are centralized? Because elections are indeed run by “non-partisan” (whatever that is supposed to mean in this context) agencies here in the US, but they are not centralized at the federal level.

Nonpartisan would mean not dependent on elected officials declaring a party.

Generally speaking, in most US states the person certifying the election result is the Secretary of State, an elected official elected while affiliated to a party. There was a whole brouhaha when Brian Kemp was running for governor of Georgia while also the Secretary of State, because that looked like a conflict of interest in a hotly contested election.

The only way to get non-partisan would be elect panel to oversee the administration of an office, and let each major party with 30% or more in office have equal # of votes. Like picking teams for school sports. It'll end up 50/50. Let the speaker of the house be the deciding vote for ties.

Judges shouldn't be appointed by the fed but be randomized by computers for a database of vetted lawyers/judges who could assume the role, and all federal judges only serve for the case they're called in for (basically reverse jury duty).

I really don’t think that that’s going to be the savings you think it is. Counting votes isn’t front-loaded with a flat rate cost or subject to duplication of effort. Having a single federal elections agency isn’t going to help if you have a super complicated ballot.

There are plenty of things to vote for though, and usually it's considered a good thing to put things on the ballot in presidential years because presidential elections have the highest turnout.

My Washington ballot this year was a double-sided single page bubble sheet. I'm not sure how much easier it's supposed to get.