Traditionally south was considered easier but as people have thrown more logistics at the NE ridge route, more have summited and the psychological barrier has come down. South is all on snow, north is lots of walking across rock like loose tiles on a roof, plus snow. South has more objective danger with falling seracs in the Khumbu icefall, north has avalanche danger below the north col but not so bad. North you drive to roadhead then walk two days to BC, south you walk at least a week to BC. North high camp is at 8300m while south high camp is just under 8000m (south col), so north summit day is shorter in height gain than south, but longer.
Both summit days have some relatively challenging climbing, but both cruxes are fixed - ropes on the south at the Hillary Step, at least one ladder on the north at the Second Step. It's no longer really true that the north is "more technical" like you sometimes here. Both routes nowadays have fixed rope basically all the way from bottom to top. This work is shared by the bigger teams on the south side, on the north side Russell Brice's Himex does it and draws contributions from other teams. North is now more crowded than south as red tape is cheaper on north.
So there is no 'easiest'.
If walking along a really narrow exposed snow ridge at 8700m freaks you out, even on a fixed rope, or you don't want to gamble in the Khumbu Icefall, then don't go to the south. If you get freaked out by teetering across loose crappy rock and scree on a 30 degree angle with a 8000ft drop beneath you, even on a fixed rope, then don't go north.
Outsidemag.com is currently running a good Q&A interview that Mark Jenkins did with Everest guides like Guy Cotter, Dave Hahn, Ed Viesturs etc.