You're smarter already than the best NNs and Genetics out there
I don't think I agree with these sentiments, but the advice is good. Neural networks and genetic algorithms are among the most promising subjects in AI research. They are the only techniques with a good likelihood of producing real emergent behavior or machine learning. However, most implementations *are* unpredictable, training intensive, and unlikely to provide a whole lot of benefit in a typical rpg.
not waste time in irrelevant methods like neural networks and genetic programming.
I would say if you want to look at something more advanced than finite state machines or scripts, the most fertile ground would be production systems. These are kind of (not really) like a large collection of interrelated if-then-else statements. The idea is to build up a collection of productions (sometimes called rules) that represent all of the 'mental' considerations of the AI.
In my opinion, this type of representation is much more authentic than a real-time plastic method like a GA or NN. Consider, during the course of a battle, it is pretty unlikely that a monster will be learning and incorporating a whole lot. It seems a bit more realistic to say that a monster or enemy has a lot of knowledge and experience (in the form of productions) that it brings into the battle, but that set of knowledge doesn't necessarily change a whole lot.