We use WordPress for many of the basic websites we build now, including one rather ambitious ecommerce project! Its easy to use, the end-user can take to learning quite a bit on their own with all the free resources out there, and with the right setup... well, its pretty darn easy to use! (Us, God-admin, User... basic editing rights)
Not sure I can list tools we use due to forum rules, but for initial load times, we run everything through tools.pingdom.com. It creates a nice waterfall graph to see which files are causing which problems, etc.
Listed below is what I find most important... as it relates to WordPress and site speed.
1 - Domain canonical.
If you choose to let WordPress handle your virtual 301 to the canonical, (going from http://example.com/ to http://www.example.com/ or the other way around) its going to delay your TTFB (time to first byte) by 1-3 seconds.
Suggest: Handle your canonical in the
actual htaccess file in the root of the domain, not the WP virtual 301 that's created in the database.
2 - MySQL Cleanup. (Note, always keep a backup of your database, there's a good plugin for that too)
If you have a lot of posts and pages, you will end up with a lot of bloat in the database of stored updates, last updated by, etc etc. Grab a "WordPress DB Optimization" plugin to clean them out weekly! It will reduce database time to first byte significantly!
If you have a very busy site, you can lookup ways to completely "disable post revision tracking" in wordpress.
3 - File-by-File, call-by-call Optimization! When you use pingdom to create your loading profile, look at every single image carefully! I once found an rss icon (16x16 pixels .png) that was almost 160k (yes, 158,000 bytes, many layers... etc, it was unreal!) in size.
We start with the largest files and simply work our way backwards. Its amazing what 30 minutes can do in this area alone!
Point.. pick through each file reference one by one, to try and reduce them tot he smallest possible size you can live with! (I aim for -10k for large images)
4 - Compress your CSS file! Its not uncommon for some WP themes to get into the 30-40k css file size. I know, thats friggin huge! I use [
cssdrive.com...] to compress the css file size and remove whitespace.
5 - W3 Cache Plugin Use it for all its worth! :-) If you are unclear about its setup, take the time to learn it or have your developer do so. Even though you set the options to cache, you still may need to walk through it and tell it WHAT TO CACHE.
We have had sites with an original load time of 8-9 seconds reduced to -2 seconds
just by optimizing the 5 things mentioned above. Its never a quick and easy process, but spending 1 hours on it now, may have positive effects in the coming weeks.