Yes, the arch is definitely good.
I had a past partner try to tickle my feet for me. It was an interesting discovery! One that has been taken much advantage of since then. :D
I’d say it’s a tie between the part where I was screaming into a pillow and the part where I was squirming around trying to fight him off and suddenly realized I was laughing!
I did! I posted a full writeup in True Tickling Stories: http://www.ticklingforum.com/showthread.php?315816-I-had-my-first-tickle-torture-session-ever-yesterday-at-age-50! There are also photos on my profile.