We're also developing web applications using python and are about to move to production.
For hosting we do it ourselves, We're a solution provider and are also offering this solution to anyone interested. If you want more info just send me a DM.
For hosting we just use uwsgi inside a docker container. We run everything in containers for scalability.
Web framework for us is currently Flask, Django is also a great option. But if you don't need the extras Django provides have a look at starlette and Sanic. 2 great frameworks similar to Flask but with higher performance. We'll be moving over our codebase to one of those two when we decided which one fits best.
For database connections we use Neomodel (OGM) which is based on neobolt. I have experience with py2neo and it works great. The Neomodel OGM is better in my opinion than the py2neo OGM but it works great if you want to directly query using cypher.
For CI/CD we run our own docker scripts on our hosts. this allows for testing as it would be the same setup as production. We use pytest for unit testing. and the deployment of everything is ran in bitbucket (cloud).
We are extremely satisfied with our setup. If you'd like more in depth info just hook me up with a message and questions you might have.