Wordpress has 1,000's of plugins for just about anything you want. Here's the dilemma.
1) There's a plugin that increases the number of connections this is how it works according to programmer:
Standard HTTP v1.1 requests only allow 2 connections, at the same time, from the same domain. This plugin will virtualize connections, through defined subdomains. You can have as many subdomains as you like, but I do recommend using a maximum of 5.
2) Then we have the normal caching program for wordpress.
3) Then we can also enable Gzip compression.
So the question is, if all things are used would that be over doing it? And if so which combination would be best?
Side note: When you upgrade wordpress it turns off the Gzip compression and you have to re-enable it. You can check you Gzip status here: http://www.gidnetwork.com/tools/gzip-test.php