In our senior league we tred something:
To avoid collissions at 2nd base we put a second real (normal height) bag directly behind the normal bag at second (along a straight line from first to second) ... The runner went to the "normal" 2nd base bag and the fielder would go to the back bag on force plays.
It totally avoided the contact at second AND got rid of any potential interference call.
Tags would be handled the same as always with runner going to "normal" bag and fielder having to tag him before he got there.
It worked well BUT there was a lot of complaining from people who did not like change (just as I'm sure there was with the extra homeplate in senior ball). We dropped the idea because of that.