If anyone wants to set up a website, you should try to give it a theme. Websites without them seem to become unorganized.
I, myself, like to form webrings (which isnt looked highly upon by google) and form relationships with other sites like mine. They give me advice and i give them advice. Both work out. My website used to be at the-herbz.mywebhut.com, but the servers were shut down for paid hosting.
Templates and css also make your site look good.
Shouldn't css be a necessity if designing with a "theme"?
It would definitely make it a hell of a lot easier. I remember once before I learned css, I made tables and I had to type font tags with the same size, color, and face parameters for every table cell (around 30). Naturally, the page ended up being 32KB of just code.
Yeah, CSS should be a neccessity.
Flash is nice to use around the site, but never for a complete site. Fully flash sites screw up search engine rankings and are generally a pain.