The most serious death threat for ELL has been:
TPTB will be watching this very closely and if we basically create a copy of ELU, they will shut ELL down before it sees the light of public beta.
EL&U had decided not to migrate questions here yet - to let us constitute ourselves, define who we are without them butting in with questions "they don't want", and instead encouraging askers to come here through comments.
Technically, so far, before a migration path is established, this is done by picking "Flag", "it needs ♦ moderator attention", "other" and typing "belongs to ELU". Once several such migrations happen, a path will be created.
Still, the question is: Should we?
My personal opinion:
While ELU has nothing to lose by not migrating "our" questions our way, and I appreciate their courtesy of "letting us define ourselves", we have everything to lose by not shaping ourselves to be different than ELU, so count my vote as "yes".