I have three different styles that I've condensed into one dude.
Assassin: (nearly) maxed out bow, with time slow (btw, +22 fire dmg, legendary ebony bow with ebony arrows = 117 dmg) with a mask of Rahgot for super-stamina }(longer bow zoom/slowtime. When coupled with a higher level sneak, I'm virtually unstoppable.
Swordsman/Samurai: high level one handed, paired with a strong sword or two. I use light armor for the movement, and it works really well. My best swords are Dawnbreaker, the Nightingale Blade, Chillrend and an upgraded Blades sword.
Mage: Archmages Robes (+50 magicka, +100% magicka regen and all spells cost 15% less to cast), Savos Aren's amulet (for the magicka boost), ring of eminent destruction (since I mostly use fire spells) and the mask or Morokei (+100% magicka regen). Basically, I just tank and spam fire/lightning spells.