The electoral college system doesn't require that they look over a long list of conditional responses and select from among them; the complexities are hidden from the voters, as you mention. I don't think the complexity of the electoral college system provides much evidence for how prospective voters would react to a complex system of voting options.

Voting systems used privately can be more complex than voting systems for public office because a more educated population may be using them.

I'd be more concerned about getting a representative pool of voters than trying to get voters to learn a new more complex system. I don't believe the difficulty of strategic voting is a major problem. On the other hand, I do think that reforms that reduce the cost of voting would be useful, and are being implemented in some states.

I like the national popular vote, but the complexities of that idea, like the electoral college, are hidden from voters; I don't think it's comparable to your ballot system.