Well, a rescan might indeed be the reason why it took your wallet an hour to load...
Looking at the lines you pasted, it looks like you loaded a different wallet.dat than "default" (initially, core will create a wallet in ~/.bitcoin/wallet.dat).
This is no problem whatsoever, but if you switch wallets, a rescan will be executed by default...
Sorry can you help me understand this? Why would loading a new wallet require a rescan? Isn't a wallet something that stores your private key and transactions or something? What is it that I'm rescanning?