That could be useful, although the framebuffer interface in Linux is becoming more capable in that respect, I just haven't taken advantage of it yet.
... better portability
At the moment, ROLF will run on anything Linux will run on, which covers most hardware. Do I want to run it on Windows? Nah!
... network transparency
I don't see that as a big advantage - how many new users is ROLF likely to gain from being able to use that facility? I can't remember the last time I ran applications on a client that was on a different machine to the one I was sitting at, other than when I was stuck with an X server in the early nineties.
It would be a minor change to add VNC support to the server, and allow remote access.
I think the advantage of having a single directory tree for all applications outweighs this, anyway.
... and a wealth of existing software work for free
but they wouldn't play nice with ROLF, when I want a consistent interface.