All in all, I find the damage reduction from Shield Energy to be inconsequential
According to Corey Bowen, a senior game designer at Wizards whos created over 30 precons and also served as lead designer on Spider-Man, the answer is complicated and changes frequently
Most of these abilities will be legal to activate as soon as attacks are declared: before blockers, as well as after blockers, after damage, or even during your second main phase
Luckily, given the prevalence of enchantment cards, these are much harder to remove than creatures so Miracle Worker is less vulnerable to board wipes than most, and Aminato's ability to surveil and give enchantment cards miracle does mitigate a lot of the top deck luck required to get it running
(d) To remove, store and insure the Lot at your expense and, in the case of storage, either at our premises or elsewhere, at the cost of 5 per lot per day
You can check in any time you like, but its very hard to leave