The enneagram gets to the root of my issues more than mbti, it is actually the most painfully honest psychological "diagnosis" I have ever related to. It talks about a fundamental, spiritual lack of connection which is driving almost everything I do, so I found it to provide deeper insight on motivation and misguidings of the ego. Mbti is probably better at describing how such issues are manifested through behaviour and the cognitive processes, while enneagram gives me more clarity on the why. I can see how solutions provided from both systems can be interchangeable, but enneagram seems to emphasise how our motivations are actually defenses from attaining a greater sense of self-liberation, which couldn't be any truer in my situation.
The INFJ description seems to gloss over how we're so empathetic and compassionate bc we want to help the world.. but I'm actually quite self-centred for an INFJ, and finding out I'm a four helped me realise why :/ I feel like INFJ is a more general description of my personality, and enneagram subtypes describe those finer distinctions between why we can't always relate to people of the same type.