It really depends on how many blueprints/RR you get and how many other buildings you need them for.As you progress through the chapters which (if any) would you recommend keeping upgraded to your current chapter?
I normally only place those that give AW or KP. And upgrade them typically in the order of which is going to give me the best other stuff.
Fire Phoenix I do first. Others like the bear, which I've never really bothered with. Too many things need pet food already.
Such a city would DOMINATE the tournament and spire with costs 1/100th as much as other cities... but would have to completely skip 3/9 tournaments and would basically suck at everything else.@Lelanya Thanks for the answer. Actually your answer made me think about a city that has no manufactories, no relic boosts, and relies solely on evolving buildings and crafting buildings for goods
Why upgrade wonders?@SoggyShorts Yeah I completely agree. Such a city will take so long to, say, activate research or build/upgrade AWs because the amount of goods required for such things does not scale with one's relic boosts (i.e., you still need the same amount of goods even though you produce less). At the same time, such a city won't meet the "Orc Wall" even if the city is a pure caterer because the demand for orcs in tournaments and spires will remain unboosted. I have started a pure cater city, and it gives me a lot to think about...
Generally, I'd upgrade my evolve event buildings like @Lelanya recommended, but Fire Phoenix is one exception I would actually put on the bottom of the list or even skip. Its feed effects are the same whether it's chapter 1 or 15 so the only big change you get from chaptering up is to get more coins or if you want portal profit instead of coin rain. The portal profit change happens in Dwarf so once you have a Dwarf level Fire Phoenix, subsequent chapter upgrades only gives you more coins...which doesn't seem like the best use of 16 RRs.Fire Phoenix I do first.