As a consequence of these numerous relevant threats which survive Lightning Bolt, any deck (besides Burn) which can enable Delirium like Deaths Shadow, UR Murktide or 4c Yorion, is better off playing Unholy Heat over Lightning Bolt nowadays
Some popular Trainer cards that you can consider adding to your deck are Nest Ball, Ultra Ball, Rare Candy, Switch, Arven, Iono, and Professor's Research
The balance between usability and visibility makes the format suitable for both casual players and competitive tournaments
Coupled with ways to get extra Treasure and the right assortment of legendary creatures, its perfectly viable, though
Any other card that will be explicited as not legal in sanctioned play by Wizards of The Coast
But I could be completely wrong about everything I just said and the card could be a beast