@hideki the blender geo-nodes is pretty impressive. I spoke to the houdini guys when blender 2.8 first launched and they were planning on making blender .hda friendly. I think the blender guys were like.... "na we can do it better" and then just made their own thing.
I have used pretty much everything at this point and I enjoy using maya / houdini the most.
I would love to just switch to blender but it feels so different from 3ds max/ XSI / maya... everything. I switched most of my hotkeys in maya to blender hotkeys. I really am hoping I can make the switch but the current UV editor in Maya vs the current UV editor in blender is no contest. Blender's biggest problem, for me, is it's shit UV support.
I think if I started in blender it would be one thing but 10+ years of production with max/maya makes it hard.
Zbrush is fine but is becoming less important these days for non-character artists.
Houdini is free and very powerful. It's not easy to learn but it can be very rewarding.