Without a doubt, Fisto deserves a 10. In terms of raw physical power, he was defintely the second "most powerful man in the universe". There was a later episode (can't remember the name offhand) where He-man wasn't around and Fisto was chosen to represent the side of good in a contest against Spikor for a number of games pieces. This suggests to me that Filmation (and perhaps Mattel as well) viewed the giant-fisted warrior as second only to He-Man when it came to brute strength.
I thought "Fisto's Forest" was a good episode. Not great, but a heck of a lot better than that circus episode.
I liked Fisto's voice. I liked the action figure's appearance. In an alternate universe, I can see Fisto being the top banana among a group of heroes.