Some folk skip the joiners, solder and file to shape, feed by bus individually, etc...some dont bother at all. You do need to be fast with plastic ties waiting to melt.
Check the flex of each whole length before setting any screws, pins, tacks, etc. Some times a rail doesnt slide well in some ties. Some extra wiggle at these points usually gets them sliding, but ive had to trim spike heads off with rails stuck firm to a tie. This is often easier if the track isnt partially fastened down.
"Stainless" and alloy metals wont always take solder, mind what you try, lol.
I like soldered connections on near everthing electrical because it works and eliminates 99% of guess work on good connections. I even solder old 3 rail at times rather than fight bad connections with a pin cleaning.
Smooth rail transitions and "sharp" joints by light bends L/R up/dwn and/or filing away any catch points of course.
Smooth trackwork becomes more necessary with smaller gauges.
Big Ho flanges might be even smaller than scale On30. I never thought about it because being true to a scale doesnt bug me. I'd run tall code and big flanges for reliability alone.
Cleaning track and wheels is a bit more of a priority on smaller gauges. Weight and even two ground rails on 3r, gives near all O gauges a connection advantage over Jr gauges in most cases. (pressure per area vs total area, is the #1 contributor to a healthy connection)
Basically near anything you can apply to running ho,n, z & 2rail, goes for On30. E.g., Flipping polarity on reverse loops is the pita on both, lol.
All the rest is pretty much "universal" model RR stuff, imo.