I'll be purchasing the Legendary Edition off Steam very soon, and I'm planning the mods that I'll want to use. First, though, I'll give some information on my PC specs:

Windows 7 64-bit OS

Intel Quad CPU Q8300

6 GB RAM

ATI Radeon HD 5570 graphics card

3828 MB VRAM

With this setup I'm fairly certain I can run the game on High at 30 FPS at least. I don't want to drop much below 30, so I imagine heavy visual mods like the ENB series are out.

And here are the mods I'm currently planning on using:

SkyUI

Enhanced Character Edit

SkyRe

Immersive Armors

Immersive Weapons

Frostfall

Realistic Needs & Diseases

Wet and Cold

Cloaks of Skyrim

Convenient Horses

Footprints

Official HD DLC texture pack

Dynavision

Imaginator

Ultra Realistic World Lighting

WATER

So basically what I'd like to ask from you guys is an expected FPS hit - specifically from the visual mods, although apparently Dynavision, Imaginator and URWL supposedly do not change FPS much, if at all - mod conflicts, patches I should be aware of to make certain mods work together better, and other mod suggestions. Thanks in advance

Depends on what types of mods you're looking for. The unofficial patches should be in everyone's list (my opinion), http://www.skyrim.nexusmods.com/mods/22650 -- makes the Companions come alive http://www.skyrim.nexusmods.com/mods/9557, http://www.skyrim.nexusmods.com/mods/18465, -- Arthmoor has several mods and all are well done, http://www.skyrim.nexusmods.com/mods/37994 , http://www.skyrim.nexusmods.com/mods/35841 -- 2 large stable quest mods.