This fan base judged Ryan Tannehill to be a fairly pedestrian QB. I've gotta go with my heart on this one and say that we are some of the worst at recognizing productive talent. Tannehill was productive. He had attributes most QBs in the league don't have, which made him a top ten QB, but we didn't recognize it even with it on the field. Now, we have Tua who has got a lot of positive attributes, as you mentioned, and he demonstrates some qualities we didn't see in Tannehill (ie. an eye for the end zone) but it also comes with a cost that Tua is not going to be as physically strong as Ryan was (ie. The Tannenator).
We've got to build the offense that Tua can command. For years, Ryan Tannehill was hamstrung by coaches and coordinators who seemingly just didn't get it. Last year was another case of a coordinator handing a rookie QB a simplified playbook that NFL defenses are not going to be waylayed by.
Take it for what it's worth, but you don't need a top 5 QB to make it to the Superbowl. You might need a top 5 something, be it defense or offense, but a top 5 position player is not one of them.