» Mon Jul 09, 2012 2:28 am
This is purely a matter of preference, but here is my two cents. I will list explanations after. First off though, you need to decide exactly what you are doing. There are certain perks that will work well if you are doing one handed, but not dual wielding. So if you plan on dual wielding, it changes some things. I'll try and point out below where it gets messy with dual wielding.
I played as an Illusionist Assassin on my Khajiit playthrough, one of the funnest I've done yet, so everything I say below is from experience.
Now, the strengths of the build are that at high levels you can manipulate an entire room full of enemies into killing each other, make them all run off into a corner so you can walk in and take the loot, leave or kill them all, or calm them down and make them continue on their merry way, again leaving them be or killing them all. With a high sneak and the invisibility spell, if you play it right you will rarely ever have to actually engage the enemy in a real fight. When you do, your sneak criticals will usually finish a fight fast.
Against dragons, illusion spells are almost useless, so you will be forced to fight them. Because the biggest weakness this build has is the lack of ranged damage options, best you can do is kite, and get them to land so you can get a few hits in. The proper shout is good for that. Oh, and you will be making good use of some of your shouts, especially Aura Whisper. First thing you do when entering a dungeon is use AW to find out what your strategy is.
With the right perks and gear, you won't need to put anything in Magicka, so you can invest into health and stamina for the entire game, which will help your survivability.
Light Armor: You don't need to invest a whole lot here, seriously. It sounds counter intuitive, but you will rarely be fighting directly, most of this style involves getting others to ignore you, fight for you or just run away. If you are concerned still about damage received, it won't hurt much to put some points into the first perk, 3 or 4. Good armor and plenty of potions can take care of what damage you will be receiving on rare occasions. With aura whisper or the detect spells from the Alteration school, you should never be caught by surprise by the enemy, and invisibility ensures that they never find you.
One Handed: Unless Dual wielding is how you want to fight, you don't need the two dual wield perks. If Dual wield is primary, don't invest a lot until later, just max out the dual wield branch, and then gradually increase the armsman. Points are better spent elsewhere, like the crit branch in the sneak skill. If you get the assassin's blade perk at 50 sneak, and wear the DB gloves, you Crit for 30x damage with one handed sneak attack. Using a summoned blade in that manner will one shot almost anything in the game on Novice to adept setting. If you put 5 points into Armsman and nothing else (the others are a bit redundant with the sneak bonuses and fight style), you are doing roughly 1800 in that single crit strike.
Conjuration: Bound sword is a novice spell. If you have Dawnguard put a point in Apprentice so you can use those spells fine as well, if not, no need to put points in that branch. However, if you want to add some ranged options (with the Deadly Aim sneak perk needed anyways to get the Assassin perk, not a bad idea, increases versatility), then go for the Adept Conjuration perk to get the Bound Bow.
I noticed that you put a point into Soul Stealer. Unless you plan on using staffs in addition to your bound weapons, or plan on giving enchanted gear to your follower, this is an unnecessary perk. Simply casting soul trap on an enemy will allow you to get the required souls for the enchanting, while saving you a valuable perk. If however, you want to put the perk in to make things easier for you with the soul trapping, go all the way and put a point into the Oblivion binding perk. You will encounter summoned enemies throughout the game, and they can make your life miserable on harder settings. If you cannot turn them, it's best to just get rid of them fast, and this perk is a 100% method of doing so.
Enchanting: I know you said you did not want to do much enchanting, but bear with me. The max level Illusion spells are very hefty on mana cost. With 100 enchanting and the extra effect perk, you can enchant your gear to reduce illusion spell cost to 0, which gives you 4 extra perks to place elsewhere. You can at the same time enchant said gear with a health or stamina regen effect, enchantments to boost damage or fortify skills (make your conjured weapons last longer). You can also enchant a pair of boots with the muffle, removing the need to use specific gear or get the muffled movement perk. More than anything else in the game, enchanting can make you very powerful. If you don't want to be bothered with levelling enchanting on your own, you can simply buy the training at each level, that gets pricey but is worth the investment if you can do it.
Alteration: Point of the build is to avoid conflict. While you will take splash damage, it won't be severe, and with the enchanted gear for Illusion reduction you will have a rather large health pool anyways. Atronach a redundant perk because of this, and same with the Magic Resistance perk, all 3 levels. That is 4 more perks to spend. Because this build is a very, very effective crowd control build, maxing out Alteration can give you one more spell to add to the arsenal, Mass Paralysis, which can be a useful tool in a crowded room, allowing you to get those assassinations in. Now, that is magicka heavy, so it wouldn't hurt to throw a couple alteration reduction enchantments on the gear as well.
http://skyrimcalculator.com/#153437
EDIT: Sorry about that, I forgot to mention the Archery tree. If you want to increase versatility and give yourself a ranged option as I mentioned under conjuration, then put points into the archery tree. The first 5 points will significantly increase your damage output with the Bound Bow, while Eagle Eye will allow you to zoom in. Since you are not a ranged character and this is only to give yourself a needed range boost, anything further up to you.
http://skyrimcalculator.com/#153438
I've spent the last 35 minutes writing this out. hope it helps!
This build also requires special gear to maximize its potential. With the Extra Effects perk from Enchanting, enchant a pair of boots with muffle and a second of your choice, although stamina regen, sneak bonus or a resist (any of them) are all good choices, as is fortify one handed. Give your gloves an enchantment to improve one handed damage and a second of your choice (both one handed and archery would help), or for your gloves simply utilize the DB shrouded gloves for the double backstab damage. If you enchant both boots and gloves with a fortify one handed, that is an extra 50% on top of perks for a whopping amount of damage. You can give your armor, headgear, amulet and rings the illusion and alteration enchantments, to remove any magicka cost from those schools.