Mith,
thank you I enjoyed reading your post. It was very well written and had a great ending. I very happy you found a group that you like and challenges you.
I am also a solo rider, due to my schedule. Also like you felt, I feel I am too slow to join a group ride
I say try ride #3, its beyond your comfort level and thats exactly what a group ride will help you do, push you beyond what you mentally think your capable of.