Regarding the shaking and the mistakes he usually makes nowadays, it's normal and understandable, I suppose.
He is almost 70, we can't expect him to be able to play like On Every Street tour when he was on his 40's.
To be honest, I think it won't take long before SoS stops being played live because he just can't play the twiddly bits at the end...just look at the Sevilla 2015 concert where he completely fucked up. But it's completely normal, considering his age and other factors. Time catches up to all of us.
I am just glad he is still recording new songs and touring, even if he doesn't need to.