18mi isn't that far
normal day on the Long Trail for me last summer.
I did Isolation as a 1.5 day trip and it has pretty nice views at the top. there is a nice spot to camp a mile or 2 from the summit.
Owls head is a long day but the slide has good views from it (not from the peak though). also has spots to camp to break it up if you need to.
To make Cabot and Waumbek slightly better, I guess Starr King and the Horn have good views so even though the bigger peaks don't have great views at least peaks in the area that you can go to do. also i'm going to do them both in one day and get it over with so the contact is minimal
what i DON'T understand is the GRID people from VFTT that do the same peaks over and over again... It is one thing going to Zealand or East Osceola with zero views once to say that you did it but doing it 12 times? or more for the really insane with multiple GRIDS (GRID= each peak in each month 576 total). There are peaks i'll do again.. Bonds ridge.. franconia ridge.. certain Presi's but if i don't go up Tecumseh again i'm ok with that. I'm moving on to the Terrifying 25 trail list that Hugh herr's kids came up with.