Enduring Innocence's second ability checks the power of the other creatures only at the moment they enter. If a creature enters with counters, those counters are included. If a creature's power is 2 or less when it enters but becomes greater than 2 while Enduring Innocence's second ability is still on the stack, you'll still draw a card when the ability resolves.

Sheep and Glimmer are both creature types. Enduring Innocence won't have those creature types when its last ability returns it to the battlefield because it won't be a creature.

A token that's a copy of Enduring Innocence won't return to the battlefield when its last ability resolves.

If a nontoken permanent that's a copy of Enduring Innocence dies while it's a creature, it will return to the battlefield as an enchantment when its last ability resolves. It won't have any card types other than enchantment.