It's a time of opportunity, of excitement, of mystery…
Ok, before getting into Elspeth, Sun's Champion 2.0, let's get a little perspective, here. Dominaria, Core Set 2019, Rivals of Ixalan, and Ixalan are all rotating out; so a number of basic assumptions might not be true anymore, and some cards that never really got the spotlight might now be poised to play defining rolls.
Barkhide Troll, for instance, might prove a pretty serious player. It's not going to be trivial to cast in some decks; but for decks that can, it's a powerful battlefield presence for just two mana that isn't a dead card against control decks. It can protect itself, pressure planeswalkers, and even benefits from which removal spells are rotating and which remain.
Red decks are losing the ability to go to the face with their three-damage spells pretty hard. A lot of potential waves could shake out from that, but it's already going to be so chaotic, with such an upheaval to the pillars of the format. What are the new pillars of the format, anyway? While some Teferis are rotating out...
...sadly, not all of them are. Teferi, Time Raveler is here for another year (including allegedly being the central character of Core Set 2021). Any decks we build for Throne of Eldraine Standard are going to need to be built with this card in mind from the ground up.
Ok, so back to big daddy.