I've thought about additions that make stealth and thievery a profession in its own right in HH.
1. Kists. Very rarely while fishing in deep ocean, you can drag up a whole container! A kist is a tiny 3x3 container that holds valuables of the ocean, like salt, driftkelp and other curious items of the deep sea. However, these treasure chests are not easy to open. They require formidable amounts of stealth x int to lockpick, can not be destroyed by hand and require very high str to destroy with a siege, varying depending on the items contained within.
2. Asthore Maps. These maps lead you to a spot somewhere nearby, where an asthore kist can be digged up from the ground. The asthore kist and the asthore map both decay at the same speed and if you don't hurry to the kist they and the map will disappear. An asthore kist is just like a deep ocean kist except that it is digged instead of fished, requires much less stealth x int to lockpick and contains far simpler items. Any fruits, mushrooms and naturally spawning spices can be contained within. Asthore maps are uncommon items that can exclusively be gained by picking up vrakgods, additionally to the usual loot. Asthore kists can NOT be digged up without the corresponding asthore map.
3. Thief/Adventurer Credo
Level: 3
Requires: Forager and Fisherman Credo
Gives:
* +10 Int
* Chance that quests additionally reward you with an Asthore Map
* +15 Stealth
* Improved lockpicking speed (assuming you can pick at all)
* Quality of all goods found in any kist increased by 30%
Quest types:
* Pick a lock x times
* Study curiosities x times
* Find item y in an asthore kist
* Find asthore maps x times
* create a stealth/int artifact
* Gain points in int/stealth
4. Burglar Credo
Level: 5
Requires: Thief and Strider Credo
Gives:
* +15 Int and +15 Stealth
* Increases quality of any kists loot by +30% (for 69% total with Thief Credo)
* Makes it significantly harder for others to spot your scents
* Reduces the time until your scents are gone by 5% (alternatively: Reduces time until the red-handed debuff is gone by 10%)
* Ability to pick any seaworthy ship's lock. Works only if the Knarr/Snekkja is either outside of a claim or on an inactive claim.
Quest types:
* Leave a crime scent of type x
* Gain points of int/stealth
* pick a wood/metal/steel lock
* pick the lock of a kist
* pick the lock of asthore maps x times
* Find asthore maps x times
* Bring asthore map related items to questgiver
* Bring int/stealth artifact to questgiver
* Pick a strongbox
* Pick a door x times