[tinkthank]

Hey thanks very much, both of you, this is very helpful. I've been doing this wrong all the time then. 15 extra gold (diff between Mausoleum and Castle) may just not be worth those 40 points if I can spend those 40 on growth, or even luck.
Also, the smaller castles come cheaper (and faster). I need at least 10 turns to pay for the difference between a 300 and a 450 castle.
This is food for thought.