I love the idea of having a more challenging Ironman gamemode without a death penalty present. My only possible issue with having a duo partner is that people burn out of RSPS and quit, in that scenario the last remaining duo partner may be discouraged in continuing to play due to the disadvantage of losing their only trading partner. Of course these players have the option of going to the classic gamemode, but what about those that don't want to?
It'd be nice for there to be some kind of distinction between duo and solo players of this new ironman mode and allow players to simply go solo if they so wish.
I think there should be an exception to this. I was thinking rather than wanting to choose a different partner for any reason, how about being given the option to choose a new partner after a certain length of prolonged activity? For example, if your duo partner isn't active (logs in) within 3 days real-time, the partnership dissolves and players are able to again choose a new one. There is still issues with this since players tend to log in to their accounts momentarily then logout causing the game to reset their activity timer.