I'm not really familiar with Riverside; I'm close to the beach. California has such a variety of geography, climate, etc., it's like Italy in that sense which I find delightful. Variety is great!
Re: Bagnoregio
No, they've not added anything to the walkway. What is different is that now they collect an entrance fee at the bottom before letting anyone walk up. It started out at 1 euro and gradually edged up to 5, last time I took a group. It was so disheartening to me to see the crowds mushrooming over the past few years. Clearly the commune needed the revenue to do some restoration work on the erosion but I suspect that after things open up some the fees will change. When I first started going there, in 1998 I would only see 3 or 4 people up top for an entire afternoon. Now, with more restaurants there are many hundreds and it's not a very big space as you know. Oh well, it will be most interesting to see what happens going forward.