Importing posts only – consequences?

I would not export and import posts as a remote publishing strategy. That is going to be a lot of trouble and probably prone to error. You will also have issues with media uploads that you will have to sync between the local and remote servers and with file URLs that you will have to constantly update with something like Velvet Blues Update URLs. I expect that there are issues that I am not think of right now, or that you yourself did not list.

What you want is XML/RPC Remote Publishing via a Weblog Client. I have never used any and so cannot recommend any, but what you describe is what that remote publishing system + client is meant to do.