"I think" is explicitly disclaiming authority. Omitting it changes the social signaling of the response significantly. Switching "wooden" for "a bit unnatural"

"I think" is explicitly disclaiming authority. Omitting it changes the social signaling of the response significantly. Switching "wooden" for "a bit unnatural" also does a disservice: "wooden" describes a specific quality of deviance. Over-all, I would definitely consider the revision stiffer and more reserved than the original.