Sway10…
You are at a point in your early career where your formal education does not prepare you for typically. Burnout is of immense importance in the first 5 years of any young designer’s career.
Those side projects can be the trigger for early career burnout so be careful on the size and ambition of such side project. Be weary of using too much company resource to accomplish these projects as well. If you manager’s manager find out that this is going on, it can create tension in the board room of especially small and medium sized firms.
It really depends on your firm’s development/launch cycle time whether you choose to leave mid project or waiting until you see it through to it is shipping. Any good experienced hiring manager knows how this works and can discern from your school project portfolio and what documented efforts you show from your current position. Documentation during the first 5 years of your career is of immense importance. Don’t wait to document your work as you not only need to be ready to jump at the next opportunity, but you need to witness how your process is changing so that you can articulate it in your next interview.
Good luck…