Well even for a simple dice i found the delay disturbing because the client can move his pawn immediatly due to predication, he dont have to wait the server response to move, but when the player throw a dice the game isnt reactive (tested with 100ms) the delay is disturbing comparing to the movement.
but yea you answered about problems i will have (2 dices/off sync), was wondering if people tried something like this with success
btw the game is still playable with 150ms but would be perfect with spawn prediction <3 (i play fast fps game i love feeling a 0 latency) even for a dice game turn by turn i want low latency 
:o (i just discovered i was an hardcore dice gamer)