Bolerus, while this is not the best thread to ask in, I'll give you my quick opinion.
KissAssist is for those that want granular control of what their bot characters do, such as defining burn routines. Pro: You have complete control over their spell/skill usage. Con: Setup is done through editing .ini files. While there is a forum with an .ini library, they are not 'plug and play' the way others are.
The CWTN (named after ChatWithThisName) plugins are extensive premade routines that can automate a majority of your characters and generally function like a decent player character. Pro: Slick GUI for settings and are (mostly) set and forget, as long as you have the right hotkeys. Cons: If you don't play on the test server, then each plugin costs $20/year. Not expensive for what you get, but that may factor into your decision.
There is also the RGMercs macro. I feel that this bridges the gap between KissAssist and CWTN plugins nicely, and can even function alongside either of them. I have personally used RGMercs for a Bard and Wizard in my group as well as CWTN plugins for the others and had great success.
If I had a better understanding of how to min/max all the classes that I play, I may enjoy KissAssist more, but generally find myself just going to the .ini library and hoping for one that matches the class and level range that I need.
With all of that considered, none are "better" than the others and pretty much come down to how much control you want over setting up and running them. I'm sure if you create a thread in the
Questions, Problems, and Bugs forum, others will be able to chime in with their recommendations. Happy Hunting!