start a new game for a wholly new playstyle.
Leave your khajiit as he is.
+24 sneak shouldn't be needed honestly... just leave the archery hood on
You might consider what magic might assist your character.
Alteration can boost your armor for fights you need it in... also has great magic resistance perks
Conjuration can provide an additional source of damage and another target for enemies to attack
Illusion is the most restrictive but potentially the most thematic. If nothing else, Silent Casting is nice when sneaking.
You should be using resto spells too... unfortunately you can't quick map a offhand weapon which makes it a bit annoying.
I wouldn't perk into destro... but I would recommend leveling it high enough to unlock cloak spells. (they don't get dmg bonus from dmg perks, and they have a long duration so cost isn't as big a deal)
with silent cast you could sneak close to an enemy, dual-cast alteration armor (nothing worse than it wearing off right before getting blasted by a 2hand attack

), then move in for the stealth kill with cloak spell in offhand (I recommend Ice to slow & stam drain enemies... but you can use any of the 3 for diff enemies) Assassinate first target (or at least high damage) then activate cloak spell, cast a summon, and then equip your off-hand weapon.