Actually, I'd only white-list Gmail and maybe Twitter. I'd prefer it if most site just served HTML to begin with.
I run with JavaScript and Cookies disabled unless white-listed, and just leave the majority of pages that won't load. Techcrunch, Engadget, and most news sites are so much faster without JS.
I might be ok with a timeout - after 30 seconds of no interaction from me, suspend the tab. Would that address your objection?