Indeed the obvious way to avoid parts of the game you don't like is to just not do them.
For feedback purposes, though this doesn't help at all.
If you have been skipping the storyline quests since chapter 9, the developers need to know why, and what can be done to make them rewarding/interesting enough for you to do them. This is a beta server: if we aren't trying to help shape the game, why are we here?
When I was doing elves I didn't have enough space to place enough elven manufactories in my city after building enough willows for mana supply (altough later I got enough space and could have done the quest for having number of elven manufactories, it was too late for me to care - I don't remember which quest I stopped at.
In S&D chapter I remember stopping at quest which required to make basic S&D resources which I didn't need, because all of my faculties were already upgraded to maximum.
In Halfings I stopped at quest which wants to build Grape farm, which I don't intend to build - I don't have space for it and I don't need it, besides 12000 mana(reward) I can get from using 4 spells (Dragon Abbey lv 6) or 2 festival traders daily mana production.
I simply don't do quests which doesn't give diamonds and wants from me either to build more race buildings than I have space for (with an exaggeration I realy don't intend to destroy half of my city just to complete some quests), or build some building which I would immediately destroy after completing the quest or produce race resources which I don't need (like in S&D chapter)
The only story quests I do are those which are completed while I do my things in the current chapter (most time I no longer even read those quests) and of course those, which gives diamonds. The rest I finish or decline at the begining of next chapter.