i don't have fond memory about cloud-init from ubuntu install in the past, sometimes it got stuck there for good. I would like the installation can be done quickly offline, or, if network is live at least timeout the stuck cloud-init and proceed when it occurs.

Cloud Init is used everywhere, probably in every cloud provider. It's very ubiquitous. I don't like it either, its syntax changed in an incompatible way between versions and simple things might require a lot of experimentation, like just creating user with password to log in. But once you're over this, it's pretty nice.