I will probably go with disqus or intensedebate. I agree Disqus can be pretty heavy and slow loading.

10Q A LOT of the 'slow loading' nature of disqus can be reduced by modifying their script so that 1) the script they add via the DOM only gets added after "onload", 2) making sure that script is loaded as ASYNC, and 3) making sure it's ONLY loaded in document.body and never in document.head (what they default to) since that makes it a BLOCKING script!

It's part of what I mean when I talk about how most of the people making these massive scripts screw up the simple stuff.

(function(d) {

    var disqus_shortName = 'SHORTNAME'; // replace with your disqus shortName

    // if you want the optional disqus_config function, add it here.

    window.addEventListener('load', function() {
        var e = d.createElement('script');
        e.src = '//' + disqus_shortName + '.disqus.com/embed.js');
        e.async = true;
        // this next one can screw up if assigned directly
        e.setAttribute('data-timestamp', new Date());
        d.body.appendChild(e);
    }, false);

})(document);

Is roughly how I load it from a SCRIPT right before /BODY... and yes, onload, NOT documentReady, that way YOUR content is shown drawn and fully styled BEFORE the scripting doo-dads even start being loaded.

If you make sure that you place ALL your scripts before </body> you can guarantee that 1) the native DOM is fully constructed enough to play with it, 2) the script does not execute as 'blocking' resulting in a faster page load, 3) it breaks you of bad habits like the halfwitted document.write or other inlined scripting that belongs at the end.

See when people include the same advertising scripts that only need to be included once. If they were all at the end you'd realize "why am I including this same script three times?!?" I see that cock-up all the blasted time!

Of course I wouldn't have the above script inside the SCRIPT tag in BODY, I'd have it in an external file so it can be cached across page-loads since much like STYLE tags the contents of SCRIPT generally have zero damned business in your HTML, and anyone telling you otherwise is an inept incompetent fool in all but the rarest of corner-cases. See turdpress and bootcrap developers for examples of such derpitude in action!

Discourse looks nice, but I don't think I want to host and maintain my own instance. IntenseDebate also looks like a good option. I'll try it out!