minimum RVR for SE IFR operations is 800m
No the minimum RVR for single
pilot ops is 800 m (unless there's an appropriate autopilot fitted), regardless of number of engines.
you will be hampered by icing as no piston singles are certified for known icing
I think there are a few. The P210 is known ice using boots, and a number of Mooneys are known ice using TKS. But as you say, it can be an issue, probably more on paper than in practice: many de-iced twins aren't going to stay in icing conditions very long.