Bonnie had had one of the rings Matt wears, couldn't she have died for Elena to wake up, then come back to life like Matt does.
They could've got another actress to play Elena when Nina Dobrev decided to leave.
It happens all the time.
No.The Gilbert's ring only work on humans, and Bonnie might still be considered supernatural. Although Bonnie no longer have her powers (she might get them back) she might still be a witch . Plus she got a extra life from Rayna who was supernatural. So either way I don't think the Gilbert's ring would work.
[love]
Kades! [/love]
Apart from the fact that Bonnie is a witch and the Gilbert ring only works on normal humans - that would still be considered a loophole and would cause both their deaths.
The entire Bonnie/Elena/Sleeping beauty plot was developed to keep Elena alive on the show but make room for Nina's departure. If they wanted to recast the actress, there were many ways they could do that :
1. body-jumping was established as far back as s2 when Klaus hijacked Alaric's body. they could have had Elena body-jump bodies for any number of reasons;
2. since Elena had the cure in her body, she couldn't be healed by vampire blood again; so they could have done the soap opera route of having her face destroyed in an accident; get 'fixed' by plastic surgery to now look different (and there are a lot of talented actresses that could look enough like nina dobrev for the swap to be feasible)
They chose not to. It was also a convenient way for Julie Plec to kill off Bonkai by demonizing Kai; and to prevent Bamon from ever happening by making Elena the victim of Bonnie's nemesis.