With regard to the tape question, I've found that the the Light bicycle bead retention ridge is ridiculously tight. I had to heat my tires to remove them. However, putting on full width tape (rather than tape that only covers the holes) smoothed out the transition from bead shelf to bead ridge. Tape can also take up some space in the rim to make inflation and air retention better. If pushing on the sidewall of the inflated TL tire causes air to rush out, you're probably playing with fire. You want the seal of the tire to be made with the bead shelf not the rim walls.
i would recommend getting tape that is 4-5mm wider than your internal width if you feel the need to do so.