Yea that sound like a suspect, the PoW that's used to prevent transaction spam. Are you running it inside a VM? Possible 1 CPU core? In your config.json what does it list for work_thread and io_thread count?
The PoW in the transaction makes sense, but I'm not sure why it's needed at address generation time.
By the way - trying to create addresses via the RPC does not appear to be functional. (Something an exchange will likely need)
Got 8 threads - again it's not that long of a time it's down. It's workable. But I imagine an exchange would need to handle at least 100 times more transactions.