Is Multi-Window even a viable possibility? I thought that was something that would need to be baked into the OS and if Microsoft didn't do it for Windows Phone 8.1 they likely won't provide a further compatibility update in the distant future for it.
Same goes for a Stylus. Doesn't Samsung have the OS built into better integrating their Wacom like Stylus? Also even if Nokia would include a Stylus they would need some useful instances for it to be applied.
My surface pro stylus would perfectly fit on my 1520 if it had the magnet for it. I'd really like to see that as maybe an option, since some people might not want a stylus, in a new Nokia/MSFT WP phablet.