With these specs:

CPU: http://pcpartpicker.com/part/intel-cpu-bx80637i73770k
Motherboard: http://pcpartpicker.com/part/gigabyte-motherboard-gaz77xud5hwb
Memory: http://pcpartpicker.com/part/gskill-memory-f312800cl9d8gbrl (I eventually want 32, I don't care that it's overkill)
Video Card: http://pcpartpicker.com/part/powercolor-video-card-ax79703gbd52dhv3
Power Supply: http://pcpartpicker.com/part/seasonic-power-supply-ssr550rm
Operating System: http://pcpartpicker.com/part/microsoft-os-glc00182
Monitor: http://pcpartpicker.com/part/asus-monitor-pb278q (Eventually)

What mods for all nine holds, and all villages look the best? The most trees, lighting, inside and out - TAVE? Better (insert place) . . . .

This doesn't affect all towns, but it does add a lot of cool and neat features:

Expanded Towns and Cities

http://www.nexusmods.com/skyrim/mods/13608

http://www.nexusmods.com/skyrim/mods/31669/?

You may want to pick up Vurts Flora Overhaul. Some of that content is in the cities.