These builds are ones that have some mixture of good clear combined with decent bossing. It won't outperform
Lightning Spear +
Rhoa Mount, but these are solid and approachable options for the majority of players.
Mercenary / Ranger / Amazon / Invoker - Crossbows (X-bow)
Crossbows were buffed quite substantially in 0.2, having their damage match that of a 2-H weapon. As such, many builds with Crossbows are viable, and most generally played on the DEX classes.
Warrior - Herald Mapping + Totem/Hammer Single Target
When it comes to Warrior builds, they usually boil down to combining a mapping setup + a bossing setup. For mapping, some combination of
Herald of Ice,
Herald of Ash, Armour Explosion and/or
Trampletoe are used.
For single-target, most builds will use
Hammer of the Gods or
Ancestral Warrior Totem +
Rolling Slam.
Witch - Chaos DoT / Minions
For Witch builds, arguably the strongest option is Chaos DoT Caster which uses skills like
Contagion,
Essence Drain, and
Dark Effigy. Conversely, you can run a Minion setup. There is a decent amount of Minion variety, but the standout minion appears to be
Skeletal Storm Mage.
Bind Spectre (Vaal Guard) and
Skeletal Frost Mage also are solid minions to build around as well.