Assassin's Kiss works with all knives, daggers, etc. Even with the skill maxed, there are swords which do more damage. Use a bow if you are so inclined, or switch back and forth depending on the situation.
Most of the doors in the catacombs are unlocked with levers, but you will start running into chests, etc. which do need to be lockpicked. Level 5 of Repair will get you the most for any loot you sell, but since money is not a problem, level 1 is good enough.
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