1: no I didn't use a blender tool
2: that's just my style. on the top of most of my letters like S and Z and stuff I curve that bar into a point. on all most all my letters I give it that bend on the main bar like the N. on the bottom of letters like S Z E C etc. I give that bar the same zig zag bend. and yeah I agree with you on the O.
3: yeah I agree, I'm gonna start changin up my style a bit. maybe vary my bar widths too.