Wow you have a lot of planning ahead!! You'll enjoy Alaska though!!
Check out old threads on here about timing/types of fishing. Lot's of great information in old threads. Sometimes more than will reply to any one thread. (like this one).
I'd tell you to plan for late July. You could fit in almost every salmon species if you were lucky depending on where you fish. Generally speaking the nicest weather.
For just a great time of year I really enjoy September. Good fishing and less people.
Good luck with your information search!!
Brooklyn to Alaska
Seward has fishing for your salmon, halibut, lodging and kayaking. Good location if you want to go to Coopers Landing for trout (45 min. drive). Homer is a really neat place also, but mainly a halibut fishery.
Send me an email if you would like specifics. There are 2 outfits here in Seward that do full day guided kayak trips. Lots of options on the Kayak trips... about $425 for a full day to Ailiak Glacier.
Lots of good fishing operations around the Kenai Penninsula and wide ranges on prices for fishing to lodging. Here is a link for what I offer. www.fishwithhill.com Some B&B's are about $85/day and local Hotels about $150/night. June to Aug 20 is great fishing. Kenai river is best in July for Kings and Sockeye salmon. Good luck with your trip.
Oh yeah. Rent an RV and you will have your lodging and transportation all in one. Best way to do it IMO.