I have an Eclipse RCP application which I am planning to write in RAP so that I can allow my users to access it on web. I have just started with RAP and have gone through what RAP can provide and what it can't. Also I have seen the demo workbench application. Seems like a good fit for my use case but I still have some questions around the feasibility and workarounds possible in RAP.
Can RAP allow ports for existing views from eclipse like Package Explorer or Navigator. Also since the workspace would be shared can there be a way around to show different projects to different users.
The short answer is NO!
The Package Explorer or Navigator views itself wouldn't be hard to port to RAP. The Workspace/Resource API is the limiting factor here, as you already guessed. For RAP, a multi-user aware resource API would be desireable that provides a workspace for each seesion.
But until now, nobody put in the effort to implement this feature.