I agree but that's a simple way out to a question that still demands a more clarified answer after this much time invested.
Do you want a QB who can overcome some deficiencies on the O line? Do you want a QB with a bit more of an aggressive inclination? Do you think that by continuing to grow and invest in our o-line we can give Tannehill what he needs to deliver us a Superbowl before he retires? I think we're approaching a time where we may need to make a decision based on some of those questions.
If you look at the Chiefs, they had an Alex Smith who was on the surface, demonstrating incredible aptitude at the QB position. The kind of play that we would most likely be very happy with had we gotten a full season of it with Tannehill (100+ Rating - 26/5 - 8 YPA - Etc..) He had led them to a number of winning seasons, playoff births, but couldn't break through. Now, I'm not telling you Mahomes is going to win a Superbowl in his first year at KC, but it's clear that he has given that team a much higher ceiling and a real shot year-in year-out at winning the SB, o-line be damned.
Just some food for thought.