The cadence of our content updates has been drastically increased from every 9 months to every 4 months, which is why we no longer have the so-called "big patches" anymore. We are now releasing 3 minor/moderate content updates per year instead of 1 massive update per year. The process changed right after the Fafurion content update in May 2019, which was about 9 months from the last update (Salvation: Etina's Fate).
We can push out more content updates per year with the change in update cadence, which also gives us less compatibility issues like being able to run proper Anniversary events around our anniversary date. The process in moving to more frequent content updates was applied to all overseas regions, so it was not something we could change.
1. Quests - The system for most non-starter/beginner quests was changed after the switch to the automed hunting system. I understand there is lack of quests and I do not have an answer at this time when we will see more quest lines (e.g. Seven Signs) added.
2. Story - Lore used to be included on the KR powerwiki and on some of the content updates pages, but we have not seen anything lately since the powerwiki was removed. I will check with the writer who works on the L2 lore to see if we can get some updates to it since we recently received lore on Death Knight and Sylph for Aden.
3. Achievements/Loot - The drops changed with our F2P transition in 2011 and again when automated hunting was introduced. We may see some future improvements to the types of items being dropped, but we will have to see once the Dev team shares more details.
4. Old NPCs/Hunting Zones - We already raised this issue up to our Dev team regarding outdated monsters still remaining in the world and requests for revamping the content. It is mainly up to the local development team to implement these hunting zone changes/revamps.
Which NPC gave you the critical error? We have an open bug in still for the teleporting critical issue with Dev.