I'm not a big fan of towing a tender. I had a couple poor experiences, one from trying to go to quickly, one from a poor towing bridle and once from a combination of things. Much rather go through a hassle and get the dink out of the water (Not perfect either).
But.. towing a 900 # 16 foot tender with a 50 hp main engine ? I don't think you should do it. How did you end up with a 30 foot boat with such low hp? I think the combined weight of your vessel and the tender exceeds the capacity of that engine. Not just weight but combined "drag".
I suspect some of our math experts will crunch the numbers and share the results with us.
pete