iCloud alternative for a calender sync I am looking for an alternative to iCloud's calender sync between my Mac and my iPhone. Like many others, I really didn't appreciate the fact that you're now forced to use iCloud to sync your calender...

So I'm looking for an alternative to either locally via USB sync my calendar with my iPhone, are to get a server on my MacBook for this purpose, which would only accept connections from my LAN. Or a totally different application for both Mac OS and iOS, syncing over USB. What I don't want is uploading my data to a server that I don't own: iCloud, Google...

I have read this alternative: sync calendar and contacts without iCloud in Mavericks but the reviews are not really good for this app... erasing instead of sync is not an option for me!

Then I was thinking about something like Radicale, i.e. setting up a server but I'm a bit worried about all the problems arising from security issues etc.

What would you suggest? Is there even something like this out there?
Update: According to developers/macrumors local sync is back in the latest beta of iTunes, and will hopefully be back in the next release as well.

Like you already said - being worried about security issues when you run the server locally is reasonable. You probably will never get your local server as safe as apple has made their iCloud Server. 
I honestly don't think your calender is so interesting that anybody would want to hack it, bur that's your decision after all. 

I currently don't know of any app that syncs via usb. Sync mate doesn't work under mavericks, but they said an update would come in "winter" this year. 

If you want to go local, I'd recommend using OS X server.