I just see this as a process... instead of launching production runs that consume resources, you sell and rebuild... At this point, I am thinking of not keeping the 5 towers required by a quest, and add more breeding buildings instead. I have not calculate yet how many breeding facilities I can run considering they need mana and seeds.
Correct
@Angeduciel, provided you don't need the towers to produce White magic and Black magic and use portal profits instead, like most will.
I did the same to put more breeding facilities around the portal. However be aware you will get another quest later on, asking to get (simultaneously, I precise) 10 towers and 10 breeding facilities. I used some teleports for the duration of that one.
Edit : Later, another quest is asking for 8 breeding facilities at level 2, then 6 facilities at level 3...
So far I kept my 10 facilities at level 2 despite their size increase (from 4x4 to 4x6). I'm reaching the point where I will increase their size again (to 5x6 then 6x6 for level 4). Considering the insane amounts of creature resources requested across the research tree, I will try to keep all of them, by making more space available.