...and to humor him, I've agreed to let him a join a game- it seemed a bit cruel to have a game like TI4 in our house and not let him play. Bearing in mind that he's adamant he wants to play on his own, what would you recommend?

a) giving him the full big kahuna burger TI experience, and bathing him in blood

b) playing a simpler game, for instance, saying "space docks always have production 3" and "each person has one vote in the agenda phase" and "you can only research unit upgrade techs, ignoring prerequisites" (if you have any other good "kids rules" for this, please let me know)

c) insist he has to play on a team with his dad

Important factors to consider:

1) we would be playing 4-player, with his dad, me, and a friend.

2) he has played some reasonably complex games already, like pandemic legacy and dominion, although his favourite game is Settlers of [redacted].