Druid Factions
 

I did a lot of hunting inside Ak'Anon and fixed all of my faction there already. The only one that I'm having trouble fixing is Eldritch Collective. Will this affect me at all or possibly stop me from completing my Epic? I know it has to do with the Gnome caster guild and hopefully that is pointless for me.

No, There's only a few factions that matter for the druid epic and that's not one of them.

Just make sure you don't kill trees, druids or certain dark/high elves and you should be ok.

Also, the gnomes don't matter at all for druid epic so all the faction fixing you done was unnecessary. I recommend checking out the druid epic page on the wiki.