Buy replacement doors and drawer fronts, refinish the cabinet frames to match. Not costly, and big difference. Big-box home centers carry them; you can order them in exact sizes for each door and drawer.

Update the countertops in a lighter color possibly in a natural stone that has a nice movement to it, then add under counter led lighting. This will lighten the room and add that modern touch that you are looking for after you refinish your cabinets.

I recently put in new countertops and sink with my oak cabinets. Pic is here:

https://www.houzz.com/photos/my-pics-work-in-progress-phvw-vp~54988842

I just finished the backsplash today: