Hawkfish are considered to be very aggressive fish, and while they may work with the fish that you have now (I had a longnose hawk with my false percs and blackcap basslet, and never had any problems), it will in all likelihood eat your coral banded shrimp. It will also limit your choices of fish in the future. I don't know which hawkfish you are thinking about, but where I live both the longnose and the flame hawkfish (2 of the most popular species of hawkfish) cost basically the same amount of money as the Flame Angel (around $40).
I like jawfish too, but they are very much a "special interest" fish. Make sure you read the Reefkeeping.com article on Jawfish, it has some good information on how to help them construct their burrows and such. However, I don't know how the jawfish will work with your purple lobster, it does not sound like a good idea. Additionally, I would think that the sand-sifting sleeper goby would be too much stress for the burrow-dwelling jawfish to handle.
As far as gobies go, I would suggest one of the firefish (any of the Nemateleotris species). I believe they are technically considered to be a wormfish/dartfish, but I have always counted them as gobies. They are about as reef safe as they come. A clown goby may also work.
BTW, both jawfish and firefish are considered to be big-time jumpers, so make sure your tank is covered in some way if you get one of them. I've also heard that hawkfish can sometimes be jumpers, but it never happened with mine.