End of May for a ride sounds good. North Cascade Hwy is a great ride too. Last time a did that I ended up with 700 miles in one day, did not get in until midnight, spent too much time in Leavenworth and ended up on Chinook pass at 11:00 PM at night in May, damm cold up there.
On a side note, anyone else heading to Laguna? A small group of us are leaving the Seattle area on Wednesday before the race. More are welcome. Would like to keep the group to about 10, plan on doing at least 600 miles the first day, route will be down I-5 to OR then Hwy 101 the rest of the way.