Although shroud is worse since it takes damage in combat, dies to mass removal and burn too, like Dawn Elemental for burn or Darksteel Sentinel for Day of Judgment
"You" refers to the controller of Curiosity, which may be different from the controller of the enchanted creature
There aren't many of these kinds of creatures, but you should definitely have a few in your deck and thankfully, they're all fairly affordable
What do you think about these results
In a Temur deck, Spider-Man 2099 could work well with The Thirteenth Doctor, given that her Paradox effect has the same trigger as Spider-Man 2099 and can be used to add more counters to him
Be careful with your Commander deck composition, so it has everything you need for an interactive game