Panther nationalized all foreign trusts in Wakanda and disolved their parliament, destabalizing their world market--he didn't do it with hacking.
Sure, Batman probably puts in an extra hour of training a day, however Panther has been doing it far longer, since he was a kid, his methods were perfected and improved long before Wayne's. The herb boosts his natural physical prowess, it does not magically grant him super abilities. He can take as much of it as he wants, if he does not exercise, his strength and speed will wane just like any man's. He cannot afford to go months without training, and he wouldn't even if he could because of his convictions.
Wakandan tech supports all the Avengers' needs. Wakanda also has its multi-purposed attack vehicles, sea worthy, capable of super sonic flight, space worthy etc. He hid one of these in a New York bay, succesfully cloaked from everyone. Anywhere he wants to go, anywhere he wants to invade he can. Wayne's business is nothing to scoff at, but it cannot compete against Panther's country's vast resources.