On your first extra turn, do it again: cast Nexus of Fate for an extra turn, then tutor it back out of your library with Mystical Tutor
The structure of a good pokemon tcg deck typically follows a balanced ratio: 12-20 Pokmon, 30-35 Trainers (including Supporters, Items, Tools, and Stadiums), and 8-15 Energy cards
Triggering landfall mechanics or just having more total mana than expected is something most people miss
Snapcaster Mage Snapcaster Mage was infamously largely playtested without flash, due to some miscommunication, which still would have been an extremely strong card
Its application here is more limited, since you ideally don't want to be bouncing your big stuff to your hand
In terms of value for money, the Draft Booster Box is the best going