I also love the idea of a MAGLEV train between Vancouver and Seattle. And yes, it would give great profile to the two principal cities of Cascadia.
However, being realistic for a moment (and I hate to rain on someone's parade) ... such a concept, even for year 2027 seems, at the present time, somehow unreasistic.
What I could see, as an "icebeaker" to get the project moving, would be a HrSR train, either with powerful diesel engines like the Amtrak Southwest Chief, or the LRT VIA train.
If something is put in place (and I think would also require raibed upgrade, big time) then the public mind will have crossed that hurdle and will theoretically strive for something better.