I really like that they are playing up the "second best" aspect mentioned in the beginning of the description, not making clonns particularly good at anything, but rather making them not be bad at anything either. I love clonns and would like to see them in-game someday.
The only problem I have really is with the Rubber Soul feature – particularly Stretch and Grow I think could benefit from lasting at least until the end of the clonn's next turn, especially if the effect of Stretch is intended to help with touch spells and such. If one activates Rubber Soul as an action and it disappears before they take another action during their next turn, it will have been for nothing. Same when triggered as a reaction.
EDIT: I am leaving the review as is but bumping it up to 5/5 both because of the author explanation and because I realised my poor reading comprehension in that the Rubber Soul is activated as a reaction while taking an action, rather than either as a reaction or as an action. The way it is written is fine, I just misunderstood the phrasing.