another vote for 20# mono here. trebles are great but i still mostly use a single hook.
i also feel enhancements help get more bites too. the addition of a small blade, rattle, or scented sponge chunk, can give you an attraction edge. i have been using a small chrome willow leaf blade on my leaders for 25years. i wouldnt still do it if i thought it was detrimental in any way. as with all fishing let the lake tell you what to use. in a clear water i opt to just use the blade. on a muddy water i mite use all three, scent, sound, and sight enhancements. scent and sound is very under utilized in ice fishing compared to open water, but it shouldnt be. scent and sound can call predators a lot farther than just sight.