I have YSlow in my browser – he says “1230K” to load page from an empty cache, no compression, no expires headers.
On most web server enabling gzip compression, and expiry information for relevant files is a couple of configuration entries. i.e. Almost no work, and it will cut your bandwidth bill. Sometimes it needs a little judgement on what can have a long expiry.
WordPress stats, statcounter and google analytics? You must really want to know who visits your site, I don’t believe the others add anything over Google Analytics.
Try Google Page speed or Yahoo YSlow – both available as browser plugins for Firefox for some other ideas.
YSlow claims some of your etags are broke, but that is getting a little technical. Start with compression and expires headers….