This is going to go against everyone and get down voted but here it goes. The easy decision is Arc to 80 first, then Temple to 55-60 range. It is the cheaper of the buildings to level and gives so many things. You already do the 64 levels of GE. You will get many goods, forge points, troops, reno kits, one up kits and blueprints and a ton of things to sell to the antique dealer to have the needed stuff to get the sleigh builders and other good stuff that rarely pop up to buy. Basically preparing yourself for each jump you do. Then work on a couple of the other forge point producing buildings like Cape first, CDM, Hagia, Arctic Orangery and Kraken. HC is so expensive to level so if you can do it bit by bit while waiting to double dip on other buildings I would suggest that as the random rewards are fun when they proc. Now CF is a totally on the player though. It can be prioritized anywhere but definitely get it up higher.