I see nothing pretentious about distinction between different disciplines since scrubs are warn by everyone from janitor to surgeons. It rather tells people what kind of services you can provide (you cannot give them meds, not your responsibility to clean a dirty toilet, etc). Embroidering is fine, but not sure how many patient will really read embroidered letters on your scrubs though (probably only those who would read your badge?). Some facilities make distinction by the color of scrubs. Distinction can be good since if there is none, people may assume PT is a nurse (which is not a big deal really, you just tell them you are not).