Well, I had a fully developed city using the maximum population and space when I reached the end of the tech tree, so basically stopped playing until new spaces and techs arrived as I had also used all the space available foe expansion in my city. Once the new tech arrived and extra spaces I started to play again, once I had researched dwarven workshop, dwarven residence and dwarven style plank manufactory, I started to undertake a massive redevelopment of my city which is still ongoing. In order to undertake this I deleted all decorations and just kept the major cultural buildings, I also enlarged my city space by a total of 6 expansions (working on a seventh but having to negotiate and trade for the expansions as troops unable to conquer any more)
At the start of the redevelopment I had 25 tier 15 residences and an indeterminate number of tier 8 residences (more than 16 but not sure how many as some have been deleted, possibly as many as 25 in total) These have now been replaced with 32 tier 16, 2 tier 17 and 7 that are working through tiers 10-15.
workshops - I had 2 tier 15, 15 tier 10 and 7 tier 6/7 which gave me enough supplies for all the needs I had, the current workshops are now 3 tier 17, 6 tier 11 to 14, 9 tier 10 and 7 tier 6 and I am still coming up short because of the redevelopment
Plank manufactories - 3 tier 15 and 3 tier 9, these have been replaced with 4 tier 16
The bulk of the additional space (150 squares) has been taken up by the addition of a level 2 portal (9 squares) , 7 marble (42 squares), 13 portal alley and 2 premium cultural (21 squares)
Also, because my redevelopment is still ongoing and will probably not be complete for at least another 2 weeks, I currently have 119 unused spaces because of the fact that buildings are constantly being upgraded