My main problem on some characters is that the 25 quest maximum is not
enough with all the different quest types that we have in the game. In the beginning
25 slots was enough but with each new system introduced, new guilds, new DLC and
expansions the quest slots fill up quickly.
There are the main quest, guild quests, expansion quests, all the daily quests,
Cyrodiil quests, Imperial City Quests, crafting quests, as well as random quests
that you run into in the overworld, delves and dungeons. Many times you don't
have time doing all of them and then you go on a guild run in IC and suddenly having
the need for 6 free slots, or in Cyrodiil where you also have 6 slots. It is not fun
abandoning kill quests where you have 16 kills to make room for other quests.
My suggestion is that they should treat Quest slots the same as Bank or Inventory
slots giving a bonus slots for people paying for ESO+