I, also, do not like those yellow lines on the rulers. If you want an accurate cut, you have to find that teeny black line space between the yellow lines to place where you want it. It's less than 1/8th inch long.
And I don't like all those teeny lines on a ruler. I have one that has a 3 inch square in a corner with 1/8th inch lines. When I pull that ruler down, I usually put back and find something else. Most rulers usually have tiny markings for 1/8 inch.
I have a slant needle and love it.
I do not own a drop-in-bobbin machine and don't want one. The 301 bobbin is on the left side and the Bernina is in front. I can lift a king size quilt out of the way and change a bobbin on the Bernina (which I need to do several times in the course of FMQing a king). You can learn to change the bobbin by feel. You don't need to see what you are doing.
If you want a spool of thread as a bobbin, you need to get an Eldredge Two Spool. They are rare, but can be found. They use the small spools that hold about 125 yards. Most bobbins hold 35 yards or less. If you think you might want to use a big spool under there, you have to think about how a stitch is made. The needle thread needs to make a big loop to go completely around the bobbin. That's what the "hook" is for. Then the take-up lever tightens up that loop again for every stitch. The bobbin can't be too big.