To answer your question. I have no clue as to what marketing strategies. Are used for your business. Only you know that particular information.
On the other hand, if you're asking everyone for their opinions on what. The best marketing strategies are so that you can implement them into your business. Well, then that would make more sense.
Furthermore, I see that you've mentioned something about bulk voice SMS. I wouldn't do it unless. I had the proper knowledge and skill set on how to use bulk voice SMS to my advantage.
Therefore my advice to you. Would be for you to talk to someone. That has more experience than you do on bulk voice SMS. That is unless you have money to burn and throw up against the wall. And you're willing to test the waters out on your own and see how things turn out.