It may be longer but it doesn't have more capacity, particularly cargo, and the 747 body is bigger overall than it is.

What is bigger?

Boeing is not making any more of them ever, almost certainly. Engine reliability has resulted in twin engine planes being usable for any flights and they are more economical. Pair that with a shift toward more direct flights between mid size cities that don't require a plane that big and the 747 has fallen out of favor with passenger airlines, and cargo is also not as interested in them.

*Not bigger...

Seems the mountain is approaching being due for more activity. Will be interesting when it happens.

In other words, their system for managing that data is not properly setup to ensure security of private data...

Mt Rainier and Mt St Helens are both totally spectacular and end of June or early July might be perfect time for wildflowers, depends how snowpack fares this spring.

The air and space museum is cool. I haven't been but people really like the San Juan islands.

Right in Seattle the Hiram Chittendon locks (Ballard locks) are actually interesting.

As others have said, Space Needle of course. Last time I was there I went up in the evening before sunset and so got to see everything in daylight and then the transition to night with the lights, was really cool. Super busy though, might be a bit problematic with a 2 year old. If you go, check out reserving ahead of time.

If you wanted to come towards Portland check out the Gorge. Could make a loop and go to Timberline Lodge as well. Nice view up there and an overall scenic drive.

Oregon coast is overall better than the Washington coast if you wanted to wind up out there.

Quite the double down man...

No lift of any sort inside MRNP. As everyone else has pointed out, the closest is at Crystal Mountain.

Red Reader here, it's fantastic.