Bitcoin-Qt is getting require large and is taking up over 10% of the space on my little laptop. Looking for an alternative, I saw Electrum. I downloaded the app and I'm able to connect to a server, but I'm wondering: what would the security implications be of not connecting to your own server?
A dishonest server could lie to you about how many bitcoins you have.
They'll be able to track your transactions/addresses and tie them to your IP address, although this is mitigated if you are using proxies (you can also go through Tor).