Lack of IDE completion is what annoyed me the most. Too easy to cause errors and typos
Very good point about lack of IDE support, I felt that too on VS Code with official Terraform plugin. However after decades of JS and PHP coding I've used to that ;)
Yong Wei Lun I haven't used or tried Pulumi yet. It looks like a direct competitor, but in this case we're after official Terraform provider developed by Atlas.