I was original drawn to Zen Buddhism and still have a soft spot for it.
I am attrached to the old Chinese Chan of the Tang and Song Dynasties, masters such as Linji, Mazu etc
What strikes me as appealing are the simple stories without complex theories. Such as the 2nd Patriarch when he was talking to some disciple who told him their mind as at unease. He (can't remember the name now) said show me your mind and I will pacify it.
Also the death poems (jisei) of mainly Japanese masters are great. I like the simplicity of language where maybe 4 chinese characters can express something which would need a whole page of English if translated.
Also I like the non-attachment to the traditional aspects of the religion, such as Buddha statues, temples, suttas etc. Sometimes I think Theravadins get too caught up in these sorts of things.
But this can be taken too far, when for example, some say we shouldn't be attached to precepts. The Japanese Daruma school of Nonin may be an example.
The more I studies Zen the more I found that these sorts of things I was attracted to were not really present in Zen. Maybe they never were, maybe they were just idealised stories that were read back into history.
In Japan, modern Zen is no different to the other sects. It is mainly just funeral business Buddhism. Monks are not really monks, but priests who may only spend a short time of intense study at a training monstery and then go back to the family temple which they inherited from their father where they will live with their wife. They will chant sutras for the dead for money as this is their job. This reminds me one of the old Zen masters said chanting Sutras with the aim of benefiting the dead was like reciting recipes to help alleviate hunger - this is the sort of stuff I love.
I was surprised to learn that Eisai or Yosai, the monk who introduced Rinzai Zen to Japan spend a lot of time chanting sutras to try to benefit the nation. It is not a matter of recent Zen changing. This was from the 1100s, Zen masters concerned with political stuff!
Another aspect which I wasn't really into was the Mahayana theology behind Zen. I could never really understand all this stuff. When you start to read some of the works of Dogen for example, it is really hard to understand without knowing much about Mahayana theories.
so this lead me to Theravada which I found to be much simpler, and closer to the original teachings of the Buddha. But I still like the simple idealistic Zen stuff.