answered:
There are two different kinds of oofs, and they’re both bad: the “Oof! Aaaah!” kind that sounds like the death throes of a dying elephant, and the “Oof! Oof!” kind that sounds like a loud car accident.
In between the two, you can use “ooh,” “oh yeah,” and “yeah” rather than “oo” or “ooh.” Use of the word “yeah” is frowned upon by many, and I can understand why, but it’s often the only option when you’re really short on words.