Travel time to and from Newfoundland will restrict your west coast options. However, these might fit - assuming you have 14 on-trail days available.
Tahoe Rim Trail. 165 mile loop. Can be done in 9 long, hard days, but 13 is more comfortable and allows for an on-trail layover day enroute. Many nice lakes for that.
Collegiate Loop (Colorado Trail and CDT). 180 mile loop through the Collegiate Wilderness.
Note elevation differences between the lower Collegiate East (CT) and the higher Collegiate West (CDT), starting from Twin Lakes. For reference purposes, the horizontal red line is at 10,000 feet (3,048 meters).
Logic strongly suggests starting from Twin Lakes and taking the Collegiate East route, returning to Twin Lakes on the Collegiate West side. I am told that Hope Pass is so named because after climbing the northbound 2.5 mile 18% grade to reach it (vs. the 3.9 miles at 16% going south), you hope you never have to do it again. Also, going north on the CDT side, your pack is almost empty when you climb Hope Pass, and it's all downhill to your car and the motel. Starting by going south on the CDT side, you get to ascend Hope Pass on day one with a full pack. Logic Rules!