The idea of something from nothing always seemed to me like pulling rabbits out of a hat. Taken in a piecemeal sense, it would seem to be completely arbitrary, and arbitrariness leads to all sorts of bad things. Nothing good is arbitrary.
Leibniz defended creation from nothing and particular providence, while insisting that God does not intervene arbitrarily in the world. Already Augustine had said that what are called miracles are only exceptions to the usual course of nature, and that God never contravenes nature in an absolute sense. This leaves room for debate as to what kinds of exceptions can occur.
If God is the pure To-Be that gives being to beings as Aquinas says, creation from nothing would seem to mean only that the giving of being is not a case of “making from”. But why is this not just called Being giving being? What does “nothing” have to do with it? Of course, the doctrine of creation from nothing long predates Aquinas, and Aquinas was a consummate diplomat in matters of doctrine. Common doctrine is not a simple matter of truth, as the dogmatists would have it; it is a kind of social compromise that helps keep the peace. Preserving accepted phrases while giving them new meaning is a time-honored diplomatic move.
Aquinas’ notion of creation was likely also in part developed to oppose the dualist teachings of the Cathars, according to whom the physical world was created by an evil power.
I have considerable sympathy for the eternity of the world, or alternatively some sort of eternal creation, such as Aquinas recognized to be logically possible. More sophisticated accounts of creation like those of Augustine and Aquinas explicitly include the creation of time, so that there would be no “time before creation”, even though they affirm a beginning. I have trouble distinguishing a beginning outside of time from eternity.