"1,977 other sites hosted on this server." Binero shared hosting is about $8 US a month?
Hosting aside, your site isn't all that heavy and performs better than many in the Joomla community:
72 http request for the frontpage
160K in JS (I don't see your js being compressed, either...could shave a lot of right there)
107K CSS
56K in flash
220K in pictures.
You can shave 35% off the pictures if you were to use Yahoo Smush.it.
If I were to put a copy of that site on, say, Rochen...even shared hosting...I think it would be much faster. Honestly, I think you are good shape, except for the hosting.