I think you can get some useful language out of these things, but you have to take the parts that are useful and leave the rest behind, including anything that makes you feel rotten or feels restrictive. The enneagram and Myers-Briggs aren't scientific, so I see no reason to let them make you feel bad. But I do find Myers-Briggs language really useful, personally. Watch a strong J and a strong P try to make plans together, and Myers-Briggs explains a lot!

As far as I know, the only scientifically validated test, the one used in academic research into personality, is the Big Five, and far fewer people seem to have heard of that one. Its dimensions are Conscientiousness, Agreeability, Neuroticism, Openness to Experience, and Extroversion, with a bunch of sub-dimensions too. You just get a score for each dimension, so it doesn't put you in a handy category, which might be why it hasn't gotten popular. It's a lot harder to remember 5 numeric scores in your head than "INFJ" (my own type).