The most obvious one is first on our list. There are many Titans fans, as well as those within the Titans facility, that would vouch for last year's rookie QB Zach Mettenberger, and argue that QB is not a need to be addressed. Even if he is the guy next year, which I would be all for; he still has questions to answer about his game. Should he be named the day 1 starter, Mettenberger will need to take big strides in his development.
On the flip side, many also think the Titans can't use their 2nd overall pick anywhere but a "franchise QB". While I don't want to dismiss this, I don't see it happening. I love Mariota as a prospect, but I think the possible allure of him will allow the Titans to stock up on picks. Either way, the Titans front office have a big decision to make.
Arguably the most critical need of this team is located at the linebacker spots, both inside and outside. Avery Williamson came in last year as a rookie and played exceptionally well, but we didn't get to see much of Zach Brown due to his early injury, and Wesley Woodyard proved that he is a role player at best. That leaves a big "?" on the inside, where the Titans desperately need a hard-nosed linebacker who can find the football in the running game, play down hill, and remain gap conscious.
That said, the bigger need is outside. The Titans relied on Derrick Morgan to supply the pass rush as well as play outside contain against the run last year from the "Leo" OLB spot. While he was often very good in this capacity, he's never going to be a dynamic pass rusher. Kamerion Wimbley posted a putrid season overall, Akeem Ayers was traded, and Shawn Phillips was released mid-season. Long-story short, the Titans didn't get anything out of the position group, and that played a big factor in their defensive performance in 2014. That OLB role is so critical to Horton's scheme, and while the sack numbers were fairly good, the Titans lacked a group of true OLB's, one's who can reliably play gap-sound run defense, and those who could provide explosive pass rush off the edge. They need to address these needs in the coming draft and free agency periods.
3. Offensive Line
After investing millions of dollars and valuable draft picks into the offensive line, there is little to show for it in Tennessee. Taylor Lewan looked excellent in his first year, and Chance Warmack came along after mid-season, but the disastrous play of Michael Oher (who knew, right?) and Andy Levitre were hurdles the Titans' offense had trouble getting over. Brian Schwenke looked decent, but by no means can it be considered a "successful" season for him either. With Michael Roos likely headed for retirement just one season after his fellow line-mate David Stewart, Tennessee's list of offensive line talent is thin. With Michael Oher a likely cut and Andy Levitre possibly being relegated to the bench (an expensive bench warmer at that), the team need to answer LG and RT, and they need to do it convincingly.
4. Coaching Philosophy
This last question is my biggest issue. While all NFL fans like to complain about their head coaches, the stubborn inflexibilities of Ken Whisenhunt in his first year with Tennessee don't lend positive attitudes heading into year two. While it may be considered a low-rung complaint, I don't think it's wise to have the HC also be the play-caller. It didn't work last year, and I don't think it will work down the road. Multiple sources have already confirmed that this aspect of the coaching won't be changing anytime soon.
Ineffectual 3rd down play-calling, questionable challenges, and a severe lack of situational and personnel awareness are elements that characterized Whisenhunt's first year. On the defense Ray Horton was slightly in over his head; I think he was more optimistic about the Titans linebackers and corners when the year started, and who can blame him? But in his own words, it was a "failed" year for his defense. Adding some dynamic talent to a starved defensive group should help going forward.
For a team with as poor of a year as they had, they seem quite unwilling to make any significant changes. We'll see how much they end up doing between now and training camp, but it's obvious that there was plenty wrong with the squad and it's management. And as much as this list is already crowded enough, the Titans ALSO need to see some significant development from the likes of Justin Hunter, Blidi Wreh-Wilson, etc, in order to compete next season.
It's going to to be a long and nigh impossible process to fix this mess in one year.