I go out alone all the time--like tomorrow.
I wouldn't worry about being "alone" because, trust me, you won't be alone out there unless you want to be.
There will be other backpackers hiking every segment of your route and day hikers on some as well.
You shouldn't have trouble hooking up with one or more of them.
You got a really great itinerary. Some long days but through
spectacular country.
You may meet someone when you pick up your permit too.
One suggestion would be to watch your water management. It's been very dry and many of the smaller streams are dry now.
pete
PS
Leave the bear bells at home.
That
constant jingling/ringing sound annoys the hell out of many people--like me
Shout, clap your hands, sing, but please...
anything but bear bells.