I switched to "vscode-restclient" about a year ago and never looked back. It has variables, everything is saved as text, and I can commit my request suite to source control for collaboration's sake.
The only reason I use Postman still is the Authentication tab has really nice helpers for getting tokens (OAuth 1/2) and signing requests HMAC. It even works with Azure Active Directory.
https://github.com/Huachao/vscode-restclient