Actually, in most cases - what do you mean by this ? If you are talking about common everyday arguments, people make, that do not know much about logic, then yeah, but you would expect that, and it applies to atheistic arguments as well.
Lets assume you are not saying something so meaningless, and are referring to actual arguments, then no; there's a boat load of valid theistic arguments. You mention "The atheist argument", this leds me to think you only know of one; the problem of evil. Well there are a lot more and the problem of evil is considered useless nowadays, although newer forms of it have arisen... they are pretty weak, and not really so popular today.
Belief ? You may yourself and also project to others a notion of irrational belief. I do not do that, I prefer rational belief based on reason and evidence. I think well enough of others to assume they base their beliefs this way also. Arguments are used for many purposes, note politicians who make up arguments to convince the voters to believe something they currently don't.
I'm pretty new to toki pona, I use the official book to guide me. I have ran into numerous problems and issues, and find that if I look in the book I find Sonja has already solved the problem. I think if you held the book in higher regard, your problems would be lessened to a large extent.
I am planning to attempt to express a lot more technical stuff that would usually require jargon or an already agreed different usage of words in that domain. I suppose I am about 20%, maybe less of the way through learning the official language at the moment. Many things I cannot express very well with such limited knowledge of the official language. Once I have either learnt enough to express that, I will, or if when I finish learning the official language, I will just have to try my best if there is no simple way to do that.
I suspect these things are included in the official language, because of how rich it is so far, but I will have to wait until I finish learning everything from the book, until I know for sure.
Follower of the official dialect of toki pona as presented in the official book; Toki Pona, The Language of Good by Sonja Lang.