I agree. Allar is starting to get on top of things with this offense and he is developing his leadership skills. If we can get him better receivers next year, I believe he will have a tremendous season next year and possibly develope into a first round pick. A year of further development and confidence will do him good.
If he leaves this year, I believe he will be taken in the 3rd round and possibly relegated to a backup role with scattered chances to start and show his stuff (see Mason Rudolph). Alternatively, he could have a great senior season and potentially increase his draft status, ala Kenny Pickett, and be given every opportunity to show he is an NFL QB. Obviously, Kenny Pickett didn't perform well enough but you need to look no further than the difference in treatment between Kenny Pickett and Mason Rudolph to see the advantage of being a higher drafted QB in the NFL.
IMO, the biggest question for Allar in his decision on whether to return is who would he be throwing to if he came back next year.