My Bernina has an extra large proprietary/nonstandard bobbin and a bobbin sensor. It's nice having the sensor but I still play bobbin chicken
It's funny how I can be sewing all week on a bobbin, but then when the sensor says 16% I have about15 minutes instead of several hours left.
I hate running out of bobbin thread, always have, and typically pre-fill multiple bobbins with my guess on how many will I need. Many years ago I pretty much stopped matching threads to fabrics, I mostly do scrappy techniques and mostly use a light slate blue/grey and light beige threads for piecing as they tend to work well with most fabrics. During piecing it can be annoying but typically minor to switch bobbins or even colors.
When I'm quilting and the stitching is visible, it can be close to tragic! So I look before I start especially if I know I have a couple hours of work ahead of me, I put in fresh bobbin.
I'm usually able to use up my remaining bobbin thread doing the hand stitching part of the binding. For what's left I will put the bobbin on a pencil and just roll off small amounts. With a quarter bobbin of a weird color and needing a bobbin, I'll take my fine embroidery scissors and cut Xs through the thread and slash it off in clumps.