Paul My experience in sea kayaking is limited.
Gulf Islands are populated and lots of boaters. Campsites can be crowded.
Johnstone Straight is a very popular area. Killer whales in abundace and you can get into remote areas easily. Lots of tidal currents(some amasingly wild currents) because of the abundance of islands and narrow channels. This is a prime area.
Southern west coast(Victoria to Bamfield) is open and unprotected towards the north and mirrors the west coast trail.
Barkley Sound is another prime area. You can find protection from groundswells and get into isolated areas. Lots of sea kayakers in the area that time of year.
North of Barkley Sound the smooth coastline of the south gives way to a multitude of fiords and islands. Many grey whales summer along this coast and the rugged nature of the area would make it my first choice. Jump off from Tofino. Groundswell should be rather small this time of year. You can watch the WAM wave forecast maps on my weather page up (
http://www.island.net/~surfer/page05.htm ) to your departure. They are quite acurate 5 days in advance and you can see the patterns developing which will give you an indication of swell to come beyond that 5 days.
Wave~Length Mag has trip accounts indexed on this page
http://www.wie.com/~wavenet/destinations.html#canstart
Timo Noko is a Fin with extensive experience on the inside passage (johnstone strait ect) Much of his website is in Finish, but you can contact him by e-mail if he isn't already off for the summer.
Look at the outfitters pages linked off
http://www.island.net/~surfer/page11c.htm
Many of them have trip iteneraries
Hope this is some help. E-mail me if you have questions. I'll do my best to find answers for them.