GENERAL

I would love to see more unpredictable things in general. Randomness and conditions can add to gameplay and make repetetive tasks more interesting.

#1 Something happens with a chance.

Fighting a boss could spawn additional minions once the boss hp is down. But only with 30% chance. Will it be the hard boss today or the usual one? Which type of minions will spawn?

Crafting could produce two items instead of one with 3% chance. Generates the "Wow! I'm so lucky!" moment when it happens without altering the gameplay balance too much.

Foraging / prospection could spawn ONE higher class node with 2% chance. For example an excellent node in a usually choice area. Or a golden node with double the time with a low chance.

#2 Something happens if something else was done first.

Enhance boss fights. Bodokin and similar bosses have these mechanics already added, kill all guards first before the boss can be attacked. Or kill the guards in a certain order. Combine with #1 and the order could change sometimes.
Or unlock access to a special boss if 3 other bosses are killed first. Those could each drop a token and a questgiver could ask for those 3 token and allow access to a new area / instance with a new boss / challenge. Why not spawn TWO bosses to fight at the same time for this challenge?

#3 Something happens in a fixed cycle.

Events could change similar to seasons, like quest chains which advance over time. A questgiver could ask you to kill Gingos for 2 days and on the third day to kill Yubos because the population grew too much without Gingos. Repeat. Simple alterations to existing quests.

One should design them in a way the player could take both, no need to remove the old mission from the player and less work for the devs.

The Pinnacle

Combine #1 #2 and #3. A certain questgiver could only spawn during winter (#2 condition) and has a different quest each winter from a set (#3 sequence), completing the quest could lead to a small followup quest offered with a low chance (#1 random) (and only with a low reward, so it doesn't punish player without it).

I'm not that familiar with the ryzom codebase nor with C++, but it could be written like this in pseudo code:

onSeasonChange() { 
  if (isWinter) {
    spawn(NPC, Quest[i]); i++; if (i > i_max) i = 0;
  }
}

onQuestComplete() { 
  if (chance(30)) StartDialog(additionalQuest);
}

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