Possible Treasure Items: 

1 - "Holy book" - if you carry this treasure item, you will always get maximum rolls from the church buff NPCs. Rolling for 8 AP is agonizing, this will gaurantee good rolls. 

2 - "Infinite Carrot" - if you carry this treasure item, your horse will auto-heal and restore its own stamina at a set interval, forever, without limit. 

3 - "Ancient Stone" - if you carry this treasure item, you can teleport from anywhere on the map, to the Ancient Stone Chamber where we start the game - available on a significant cooldown.

4 - "Indestructible Stone" - if you carry this treasure item, your gear will never lose durability through use. Repairing is no longer necessary for you.  

5 - "Oasis Panacea" - this will be like the infinite potions, for use with Fairy Inexhaustible Well. You will be immune to desert heatsickness and hypothermia if you have this item loaded for your fairy.

Feature/QoL changes: 

1 - Agris potions. Alustin the alchemist will now allow you to convert 100k Agris into an Agris Potion. Agris Potions can be used on a 12 hour cooldown and will restore 20k Agris to you. Agris Potions, like Energy Potions, can be listed on the Central Marketplace and purchased by other players. 

2 - Expanded Family Inventory. Infinite Potions and other Treasure items can be stored in Family Inventory.

3 - Imperial Delivery / Trade while on Tagged characters. It is not fun to be prevented from doing Imperial Delivery if you have a gear-copied tagged character. Remove this limitation. 

4 - "spare" Fairy slot. Allow an option to keep a secondary, inactive fairy. This way, you can continue to "roll" your second fairy stats, without fear of losing your primary fairy. Additionally, implement exciting new fairy abilities to roll for. This will improve demand across the entire playerbase for more rerolling of fairy stats, for more fairy-related items, and for more cheap gear for fairies to consume to grow. 

Item changes:
1 - change how the Blackstar quests work to acquire and create Blackstar weapons & armors. The new systems in place to earn PEN gear makes Blackstar armors feel unusually obsolete, like they are dead-end items that are both difficult/limited to make and questionable to use. I have sold many blackstar items in the past but now I am sitting on multiple Specter's Energy uncertain if I should even bother crafting more. 

2 - add a lifeskill Mastery bonus (100) directly to all Item collection loot scrolls, so that these are useful to lifeskillers too. 

3 - remove all direct drops/rewards of Caphras stones, and significantly increase the droprate & occurrence of Ancient Spirit Dust instead. This will further increase the demand for, and supply shortage of, black stones. Why? I don't know, but I like the idea of black stones being an analogy/metaphor for real life oil - a valuable commodity that we can never get enough of. 

4 - black stone simplification. Remove the concept of separate Sharp/Hard Black Crystal Shard, separate Weapon & Armor Black Stones, and also remove the concept of separate Concentrated Weapon and Armor blackstones. Let there be simply: Black Stone, Black Crystal Shard, Concentrated Black Stone. There are too many stones. It feels messy and unnecessary. 

5 - remove the concept of weapon exchange coupons, and remove class-specific listings of weapons in the central marketplace. Devise a method to convert any class-specific weapon into a generic weapon "box" - perhaps by paying an NPC a certain percentage of the item's value in raw silver.  Then organize the marketplace for weapons as boxes - For example, you buy a "PEN Dandelion Awakening Weapon Box" from a singular listing on the marketplace, and you open it on any character you choose to get the Pen Dandelion weapon of their class. 

Shop changes: 

1 - combine Value Pack, Kamasylve Blessing, Book of Old Moon into one all-encompassing "Premium Pack." Shop simplicity will feel less frustratingly "nickle-and-dime" to players. Additionally, make the marketplace Silver value of the new combined Premium Pack be the best pearl-silver ratio, so that more players choose to purchase these Premium packs solely to supply them to the in-game marketplace. Your playerbase will happily advertise to prospective players that BDO is even more "free2play friendly" and people will probably happily buy the combine pack at a much higher rate than people buy each type of pack individually. 

I like those treasure item ideas, except the ancient stone and have my doubts about the indestructible stone. But it's a treasure item and not easy to get so not like this would face out branding of items.

I agree with this the most. I had thought about it a while back but differently, perhaps phase out all these items and make a pack that you can choose x amount of buffs out of the 26 benefits provided by Blessing of Kamasylve, Value Pack and Book of Old Moon. The cost of the pack depends on the amount of buffs the Pack gives you and duration.

For example: 

"Jack of all Trades S" 5 Buffs, 15 days Duration. 1250 Pearls.

"Jack of all Trades M" 8 Buffs, 30 days Duration, 1600 Pearls

"Jack of all Trades L" 12 Buffs, 90 days Duration,  4500 Pearls

"Jack of all Trades XL" 15 Buffs, 180 days Duration,  8600 Pearls

You obtain this "Jack of all Trades Pack M" and from the following list. You choose as an example those with a Checkmark. Your Pack becomes active with the buffs selected and cannot be changed for the duration of the item (Or there is a limit amount of changes based on the size of your pack, with a cooldown.)

☑️ - Inventory Slot +16
☐ - Storage Slot +16
☑️ - Combat/Skill/Life/Mount EXP +30%
☐ - Distant Node Investment (Consumes 10 Energy)
☑️- Weight Limit +200 LT
☑️ - +30% Marketplace Sales upon Silver Collection (Excluding Pearl Items)
☐ - Unlimited use of Merv's Palette
☐ - Unlimited Beauty Salon
☐ - Barter Refresh Count +1

☐ - Combat EXP +100%
☐ - Skill EXP +50%
☑️ - Life EXP +50%
☐ - Reset (enhanced) skills freely
☐ - Change skill add-ons freely
☐ - Change Skill Preset in Safe Zone (Cooldown: 10 min)
☐ - Buy villa scrolls via your campsite without having a villa invitation
☑️ - Stable slot +1 (for all regions)
☐ - Wharf slot +1 (for all regions)

☐ - Energy Recovery +2
☑️ - Item Drop Rate +20%
☑️ - Central Market Warehouse Capacity +2,000 VT
☐ - Transaction Maid Volume Limit +100 VT
☐ - Storage Transport Weight Limit +1,500 LT
☐ - Required Parley for Barter -10%
☐ - Allows you to remotely check or skip Special Barter

This would streamline the complex system of these packs/blessings/books. However... It would not surprise me if it's designed this way so you spend way more than you originally would and have buffs you barely use...