One of the most fun builds i ever played , finding dwemer armor with good enchantments is not hard,you will reach the armor cap in no time with Visage of Mzund high AR, high Smithing from all the dwarven metals you find and craft plus Ancient Knowledge  , also your legendary crossbow will deal great damage because of improvement with high Smithing (crafting dozens of Dwemer Armors will get you Smithing 100 quite fast - you can sell them to Gunmar afterwards for extra Smithing training) . The follower will have legendary armor and weapons also, only i removed range weapons from mine (Mjol), i wanted her to tank with a 2H weapon, not shooting bolts; the sphere that you get as a pet is also great, spiders are just flavor . 

Also, a house in Markarth is of the essence for this build 

I was just thinking of doing this character build but you beat me to it by a long shot. Darn. I was going to use ebony armor though, and a variety of bows... </3

I don't know if you already know this or someone else has said, but you can get enchanted crossbows if you complete all of the Ancient Tech quests before you rescue Florentius, depending on your level The Charmed Vigilants will carry enchanted Dwarven Crossbows, I got a Dwarven Crossbow of Immobilizing and a Dwarven Crossbow of Thunderbolts when I went to rescue him