The fighting style of the Altmer Ninja class is to use power attacks and sprinting at will. Statistics are 3 Health, 3 Magicka and 4 Stamina per level. Armor is enchanted to improve stamina. Restoration and potions are used in battle to regenerate stamina constantly. Sprinting is used tactically. All kinds of power attacks are mastered and used as often as possible.
Skills:
One handed - The Ninja starts off with axes to cause bleeding, then switches to maces or swords depending on the armor rating of the target. Of course all perks in this tree should be taken, focusing on the power attack branch.
Light armor - Sprinting, including sprinting power attacks, is a necessity.
Restoration - Perks to focus on are reduction of magic cost, restoring stamina and regenerating magicka faster
Alteration - For extra protection in emergencies, opening locks, breathing underwater
Destruction - For long range attacks
Sneak - For backstab
Enchanting - Statistic buffs and soul-trapping for weapon recharge
Alchemy - For poison and statistic regeneration
At high level, Smithing can be added