The D will RushYa, Like Moscow
I think alot depends on how much they like Matt Moore. If they think Matt Moore can progress next season, then going with Tannehill seems like the best fit. If they feel Matt Moore has hit his ceiling, maybe a more seasoned Brandon Weeden, a guy who would be able to come in sooner, would be the better fit.
All this talk of QB's, my biggest concern is with the evaluation of these QB's, from who you already have to what you possibly can obtain.
Tannehill is the bigger gamble but I think clearly he offers the biggest reward longterm.