Tried to install the Ethereum Wallet yesterday.

It seems to have a serious first start issue. If for any chance it get's the wrong nodes on first start up it is stuck at around 3 mil open blocks.
It always sees a few nodes 1 to 3 and the 3 mil change up and down but never synchs.

After fighting it a few hours I backed up my files and wiped all files except the one in keystore.
(I found no option/console to tell ethereum to resynch the block chain or do anything for a recovery!?)
Installed it again and now it synchronizes finally.

Question: Is my passwort and the file in the Ethereum/keystore the only file I need to backup or do I need to backup more?

I still haven't figured out what Ethereum is really usefull for... but seems a lot see a value in it so I best don't ignore it completly. I need it for diversifications.