hey there,
I am playing a lot of commander and I also had trouble to deal with boardwipes.
Ever thought about cards, wich win you the game after a Boardwipe?
Since you are in Lategame when a board whipe resolves anyways, how about:
rise of the dark realms,
living death,
second sunrise, or protect with
Boros Charm, selfess spirit?
This wont help against
Terminus and mercyless eviction, but against most massremoval
Also, try to hold back something and do not overextend the board
kind regards Hawjik