I'm a bit confused by your last message. You quote part of my reply, then a question appears in the quote, but I think the question is something new, not part of the quote? I'll go with that.
Would manual Synchronization (via the File menu) still be available?
No. It has to be done thru the Transfer menu in the Database Sharing Options wizard. There is no synchronization -- only upload or download. In my application, I occasionally download data to the client to look at it, but that is not part of the normal operation of the database. There is code on the server that automatically transfers summarized information from this database into other databases at midnight, and also archives the data in logs and deletes old data.
I am constantly modifying/enhancing many items which currently have many benefits from being shared
Yep, this database I am talking about was a pain to set up. I am not going to argue that this is super convenient or easy. However, this was not the scenario that Panorama Server was designed for. So you can bend it out of shape to get this done, but it is definitely going to be more work on your part. I still think this was a lot easier to do in Panorama than in other programs -- I did very seriously look at using other database programs for this particular application. By the way, if you do some google searches, you'll find that applications requiring massive database deletions are a difficult problem in any database program, at least if done at large scale and performance is an issue. In single user mode Panorama can do the deletions in almost zero time, but that comes at a cost of making it somewhat difficult to access the data off the server.
For my application I was able to do most of the development work in single user mode on a client, then I transferred it to the server. It turns out I had an archived data stream so I was able to run simulations on my local computer with real data to debug the code. Once it was working, I haven't have to change it at all. This database is part of a set, all of the other databases in the set use regular shared databases. Summarized data from the intake database gets passed along into the other databases. Only the intake database is not shared. Since it is handling data that is coming in in a fixed format that doesn't change, it hasn't needed to change either. Hopefully you could also your design your intake database with enough flexibility that it wouldn't need to change much after deployment.