I agree that a two weapon rogue is the way to go. You would then want to take the knife master archetype which will jack up your sneak attack damage to d8's instead of d6's with the dagger. Then take opportunist and other stuff designed to get you more attacks so you can proc that sneak attack more. For magic, invest in fogcutting lenses because obscuring mist/fog cloud is everyone's favorite low cost way of denying rogues sneak attack.
Here's a sample 20 point buy Varisian knife master who uses starknives (proficiency courtesy Varisian Tattoo) for the x3 crit and 20' range and because they're cool red hood style toys. Using piranha strike you get-2/+4 with each, the agile starknife adds dex to damage, sneak attack's +3d8 with each one.
Stabby Stabberton
Male Human (Varisian) Rogue (Knife
Master) 6
CG Medium Humanoid (human)
Init +6; Senses
Perception +10
Defense
AC 21,
touch 16, flat-footed 16 (+5 armor, +4 Dex, +1 deflection, +1
dodge)
hp 43 (6d8+12)
Fort +5, Ref +10,
Will +4; +1 trait bonus vs. charm and compulsion
Defensive Abilities blade sense +2, evasion, uncanny dodge
Offense
Speed 30 ft.
Melee +1
Agile Starknife +8 (1d4+5/x3) and
+1 Starknife
+8 (1d4+1/x3) or
Starknife +9 (1d4/x3), 20'
Special Attacks
sneak attack +3d8/+3d4
Statistics
Str
10, Dex 19, Con 14, Int 13, Wis 12,
Cha 10
Base Atk +4; CMB +4; CMD 20
Feats Combat Reflexes (5 AoO/round), Dodge, Piranha Strike
-2/+4, Quick Draw, Two-weapon Fighting, Weapon Finesse, Weapon Focus (Starknife)
Traits Reactionary, Varisian Tattoo
Skills Acrobatics +13, Appraise +8, Bluff +8, Climb +8, Disable
Device +12, Disguise +4, Escape Artist +8, Knowledge (dungeoneering)
+8, Knowledge (local) +8, Perception +10, Sense Motive +5, Sleight of Hand +8 (+11 to conceal a light blade), Stealth +13, Swim +8, Use
Magic Device +9
Languages Common, Goblin, Varisian
SQ hidden blade +3, rogue talents (combat trick, finesse rogue,
resiliency [1/day], weapon training)
Combat Gear Acid,
Alchemist's fire, Tanglefoot bag, Thunderstone; Other Gear +1
Mithral Shirt, +1 Agile Starknife, +1 Starknife, Dagger, Starknife,
Cloak of resistance +1, Ring of protection +1, 124 GP
Special Abilities
Blade Sense +2 (Ex) +2
dodge bonus to AC vs. attacks made against you with light blades
Combat Reflexes (5 AoO/round) Can make extra attacks of
opportunity/rd, and even when flat-footed.
Evasion (Ex) If
you succeed at a Reflex save for half damage, you take none
instead.
Hidden Blade +3 +3 bonus on Slight of Hand checks
to conceal a light blade.
Piranha Strike -2/+4 You can
subtract from your attack roll to add to your damage with light
weapons.
Quick Draw Draw weapon as a free action (or move
if hidden weapon). Throw at full rate of attacks.
Resiliency
(1/day) (Ex) When brought to 0 Hp or less, gain 6 temporary Hp for
1 min.
Sneak Attack +3d8/+3d4 +3d8 damage with a
dagger-like weapon if you flank your target or your target is
flat-footed.
Uncanny Dodge (Ex) Retain Dex bonus to AC when
flat-footed.
Varisian Tattoo +1 trait bonus on saving
throws against charm and compulsion effects.
Some quick searches show me that the internet is full of historical accounts, movies, TV-shows, and stories about kings, rulers, and other such nobility and what they do during their day. I am sure you are aware of this as well, so I understand that you want an answer in the context of a role playing game.
The King can do whatever he wants
Regardless of what is expected of him the character can always decide he just wants to go riding through the woods, or go down to the tavern and get drunk, or take up pottery lessons. But that is not something new in role playing games, it's just important to make a note of it. Moving onto...
Everyone wants to meet the King
As a ruler, everyone will want to meet with you, talk to you, and get your feedback, authorization, or approval. From commoners seeking an audience, merchants seeking trade, foreign dignitaries, and your own councilmen. This takes up time, and your day is probably full of scheduled meetings with important people, while those below you take care of the less important people. Which leads to...
You need to lead
Being a leader means you actually need to do some leading. This can be as simple as just writing decrees from your bed, or going to council meetings and discussing with your council on the affairs of the kingdom. It's all fine that you have allocated and delegated most of your power down to various minions - but you need to keep guiding them. They will have daily, weekly, monthly, and yearly reports for you. You can further direct your kingdom by getting updates on the various aspects within your kingdom - and these meetings with your minions are how you get that knowledge. You might want to change policies, or even change the minion taking care of the policy. But that is also part of...
Secrets!
What good is a king without some secrets? whether its your spies, your mistress, or even your spies mistress - there are some things that a King has to deal with that shouldn't be made public knowledge, hiding these things requires finesse! You need to be able to slip away from people, arrange private meetings, send secret letters, and all this with your schedule full, and people everywhere looking for you. So naturally...
You need to have fun!
What good is being a king when you can't hold a royal ball? Or a feast? Or a tournament? Yes most of the work is done by someone else - but you are the vision behind it. You decide what and where and who, and someone else will build it and manage it. But you need to make sure that you have enough money, which leads to...
You're on a budget!
You are the King yes.. and you are the one in charge.. but only as long as everyone is in line... which usually requires money. Money that you collect through taxes, trade, tithes, and adventures. But you also spend this money - and it is your job to either balance this spending or have someone else do it. And if that doesn't work out for you, you might need to ask for help...
Dealing with other Kings
You will need to send emissaries, or even travel yourself. You will be trading, warring, politicking, marrying children to each other and getting into lots of untold naughtiness. That is a fact.
So if you want to know what a King does with his time? I answer you - What time??
Best Answer
Officially, you are better with a Lyre of Building than trying to find rules for undead laborer to build towns. The topic of wether mindless creatures can take simple orders or not is subject to GM fiat and normally will see table variation.
Now, if you happen to be interested on what Jason Nelson, the creator of the original kingdom building system for the Kingmaker AP, has designed for undead workers, you should take a look on the Ultimate Ruleship (3rd party book from Legendary Games). Which, among other things that improve the kingdom building system, brings some magical improvements like the Deathless Laborers, Animated Automation (animated objects as laborers), Hallow/Unhallow (to cast permanent spells on a building) and Permanent Teleportation Circle (exactly what the name says):
As for your question: Yes, it does limit their work.
By how much: That's up to your GM.
Some GM's will say that mindless creatures cannot do anything related to math, or measure distance, or measure weight. Others will say that they can do anything as long as you explain it properly. While others will say that they can do anything as long as they are being supervised and directed, as long as someone with the proper Profession or Craft skill is directing them.
Crafting a simple item (like a spoon) is a DC 5 Craft check, while crafting something a little more complex (like an iron pot) is a DC 10 craft check. Considering that mindless creatures make Int-based checks with a +0 bonus, and that Craft can be used untrained, that means they could craft simple items with a take 10 on their skill check. If they have the proper tools (at least +2 bonus), they could even make simple weapons, like long bows and short swords, or leather armors and shields.