If you feel that your opponent is playing slowly in an attempt to stop you from winning then you are within your rights to ask them to speed up or in extreme cases you can call a judge to ask them to hurry up a bit
Zen Miyaji-Thorne, one of the creators of Rainbow Dredge, took a look at the history of the deck and its current state in the meta
If Cursed Wombat leaves the battlefield while a spell or ability that would put one or more +1/+1 counters on one or more permanents you control is still on the stack, those permanents won't have the additional ability granted by Cursed Wombat when those counters would be put on those permanents, so that additional ability won't trigger
Creatures get tapped when they attack, but not when they defend, and a tapped creature cannot be used to defend in turn
Or "White Legends Tins" in the summer with Lugia, Reshiram, and Zacian
Thankfully, we dont just have to speculate about which cards wed think would make a good reprint