Good to hear back from you.
Well, this is PA, not exactly the land of progressive planning. PennDOT has changed their construction standards in the last 10-15 years to include emergency pull off lanes on state roads that will double as bike lanes, gradually re-constructing existing roads to those standards, but they have a long way to go. As to speedy drivers, well yes. After a while we all figure out that the suggested speed limits for curves are 10 mph slower than what you can actually take them at, so why would we drive any differently on the straightaways? :-)
You're off Route G more than I expected, so I don't have first hand knowledge of those parts. However, I did check PennDOT's traffic volume maps to get some feel for those parts of the route. That said, I think you probably don't need to be too concerned. If you want to check those maps yourself, here's the link.
http://www.dot.state.pa.us/Internet/Bureaus/pdPlanRes.nsf/infoBPRTrafficInfoTrafficVolumeMapI can't comment on the road out from Jersey Shore to Route 44 as I came up the other way from Lock Haven. However, the traffic maps suggest this is going to be basic small city urban riding out to Route 44.
Once you turn right onto Route 44, as I recall the road is fairly wide, there isn't much shoulder, but the traffic is modest and the sight clearances are fine since the Pine Creek valley has widened out here. You're only on the road 2-3 miles before you come to the rail trail.
Once you come off the trail onto Route 6, the traffic is again modest, but you have a 3-4 foot shoulder to ride on. I turned off at the intersection with 287 and didn't have time to go into Wellsboro. The traffic maps suggest that this strech of 6 is somewhat busy, and I don't know what kind of shoulder you may have here.
I assume you will be going out Charlestown Road to get to the camp ground. The traffic maps indicate that these are local access roads with very light traffic -- a few hundred cars in each direction every day.
Route 287 into Tioga is wide and flat with modest traffic. I don't recall any shoulder, but the lane is so wide and the sight clearances are so good that you really don't need one.
When I rode it, 287 ended in Tioga and you took Route 15. That was a busy road. However, they were in the process of finishing a 4 lane version of Route 15 that has since been completed. (Getting through the construction on a bicycle was lots of fun.) The old two lane version was renamed as an extension of 287. It appears now to be basically a main connector road between Tioga and Lawrenceville for local traffic with a couple thousand cars in each direction every day. As I recall it has shoulders, since the trucks could blow by me fast enough that I kept getting hit by their backdraft. That probably is no longer an issue with the new four lane.
PA law provides that bicycles shall keep to the right as far as is practicable. How far is practicable? You know the drill I'm sure -- use your common sense and judgment depending upon the situation, otherwise ride far enough to the inside of the lane to force them to pass you like a car, and take the lane when necessary. You'll be fine. Don't worry.
By the way, I didn't plan a trip this year. I'm envious.
P.S. Bring bug dope for the trail. It's fairly buggy.