[Gregstrom]

1: The risk builds with time, and varies by item. Limited use of powerful items is pretty low in risk, and Lightless Lanterns are pretty safe overall. It's all about cost/benefit ratio, though. Cursed horror marking items are an eventual death sentence most of the time, so you need to make sure that the benefit outweighs the eventual loss of the items and holder. So... turning a S4 cap-only mage into a wish spammer might be a good use if you have several available. If you only have one and don't expect to see another any time soon, keep him safe and empower instead.

2. Your pretender isn't sacred, so I think giving it the Ark is a bad (and painful) idea. This does seem silly, but there you go.

4: Trollification is often a benefit, and only really detrimental in a few cases (Abysia, underwater, etc...).

5: I always assumed Nethgul had a spell list and just chose from it like a normal mage would choose from their available spells.