Hitting level 2 should be within the first 2-4 hours
Level 3 within another 6-8 hours

I’d say finishing up Chapter 1 could put the player closer to level 5 (possibly fringe 6 if you did close go evrything.

Chapter 2 levels 5-10ish
Chapter 3 finishing up the game around 14
Future DLC taking us up to 17
Would be interesting additional DLC taking up to 20 but that makes for playing god-like characters and id imagine terribly difficult for a computer to properly balance and manage.

I’d really love for this engine to be incorporated in official modules as well such as LMoP, etc.