Hi Andreas,
I am familiar with Yuan Tze's system but someone who is a proper student would be better at giving you advice. I have studied almost 1/2 of his system, including his most advanced qigong forms. I do know a few of his students and it has been transformational for them.
What I can say is it's very advanced and well rounded compared to most qigong/nei dan systems/teachers I have studied (which tend to be less well rounded and less complete), and a small number of his students, and Yuan Tze himself are supposed to be awakened / achieved self realisation.
In terms of qigong, the first 3 levels focus on qigong, with Level 3 being a very advanced Nei dan practice for energetic awakening. Level 3 is not considered crucial for healing or self realisation however. The later levels (4, 5 and 6) focus on awakening the heart , and working with unhelpful patterns of consciousness and the mind, both of which are considered important for expanding one's consciousness and self realisation in his system.
You are not expected to do all the teachings however, there is too much, and it's not considered necessary for healing and expansion of consciousness in his system. Some of his awakened students just focused on a few areas. Finding a teacher would probably be the easiest thing so you can work out what would be useful for you.
Given the high level of teachings in Ren Xue, I am surprised this teacher hasn't been mentioned here in this forum until now. However he already has a large following in the US, Australia, Europe, New Zealand etc, so perhaps it wasn't relevant.
One thing I can say about him is he has real integrity and humbleness (as you mentioned) and his students and his system are imbued with those qualities.
