I'd add that the Amazons would probably be much like the Japanese, in regards with technology- having been introduced to a new source, they'd re-invent the hell out of it. I think that Trevor's introduction would cause a major catalyst in technological development, something like, "Hmm, well, remember those old projects that we had, gunpowder and refining steel and such, the ones we cancelled because it'd be developmentally unfeasible? I think there's a future..." Now imagine the contact with the greater world. The Amazons would totally be the Japan of the DCU.
I do object to the idea of magi-tech however. DCU Magic laws have pretty ingrained bartering rules. To try to barter for the ability to create, say, magically-replenished crossbows, or Light-speed arrows...that would cost more than an arm and a leg. There is the whole divine aspect of Themyscira, but I think that can be explained away by the gods saying, "Well, you don't REALLY need it."
I think something to take into mind is that all our technological developments have occurred under generally horrifying circumstances - war being a great catalyst. It requires lots of experimentation, lots of failures, and lots of ecological damage. The Amazonian know-how can find ways to do it probably smarter and with less waste, but that requires more resources than I think they are naturally given. Progress would be smarter but possibly as equally slowly as our own cultures, because of the lack of wide tracts of virgin resources, cultural interaction, etc.
Update: I discovered that the Greeks supposedly DID have an automatic crossbow weapon. The Polybolos (look it up on wiki!) Mind you, it was a ballista sized weapon, but Amazonian know-how would have minituarized it, as well as developing the existing one to some stupendously horrific capabilities. So there exists even a Grecian basis! Further note: The chinese repeating crossbow was inaccurate, not terribly powerful vs. heavy armor, and easily wrecked. I'm sure the Amazonian one would be pretty brilliant. Question: Does anyone know how fast/powerful a crossbow is/was? A modern bow with equivalent tensile strength? Just wondering whether these would be actually Level III body-armor piercing or not.