When an effect returns the exiled card "under your control," you control it indefinitely after that. If you had temporarily gained control of a creature, it won't return to its previous controller. In a multiplayer game, if a player leaves the game, all cards that player owns leave as well. If you leave the game, a creature you took with Restoration Angel's effect is exiled.

Once the exiled creature returns, it's considered a new object with no relation to the object that it was. Auras attached to the exiled creature will be put into their owners' graveyards. Equipment attached to the exiled creature will become unattached and remain on the battlefield. Any counters on the exiled creature will cease to exist.

If a token is exiled this way, it will cease to exist and won't return to the battlefield.