DAVIE, Fla. -- The Miami Dolphins have been planning for the 2020 offseason for a long time, and in the coming months, the next step in the rebuild continues with more roster turnover.

With 14 projected NFL draft picks (including three first-round picks) and a projected $100 million-plus in salary-cap space, Dolphins general manager Chris Grier has a bevy of options to overhaul the team that went 5-11 in 2019.

This is the most important offseason for the Miami franchise in recent memory because of all those options, primarily centered on what the Dolphins do at the quarterback position.

Here's the most pertinent topics as we await free agency, the draft, minicamps and more:

Is it QB or bust for Miami in the upcoming draft?

The Dolphins have been searching for their franchise quarterback since Dan Marino retired 20 years ago. After passing on quarterbacks in the top six rounds in every draft since selecting Ryan Tannehill in 2012, it appears time for Miami to take its shot. Or, is it?

The Dolphins are not obligated to draft a QB in 2020, according to Grier, who has said: "I'm not trivializing the quarterback position. We're going to investigate that hard just like every position in the draft and free agency."

It's unclear whether the Dolphins would kick the can down the road another year, or if this is just gamesmanship in order to not give other teams around them the ultimate draft-day leverage. The Dolphins have plenty of position needs such as offensive tackle, edge rusher and running back, but nothing moves the needle like a future franchise quarterback.

The prospect to watch is Alabama quarterback Tua Tagovailoa, who could be available when Miami picks at No. 5. The Dolphins might be considered the favorites to land Tagovailoa considering he has been tied to them for close to a year (i.e., #TankforTua) and many folks in league circles believe the Cincinnati Bengals will draft LSU QB Joe Burrow with the No. 1 pick, leaving Tagovailoa or Oregon's Justin Herbert as the next best options.

What happens with the Dolphins' current QBs?

Grier said the plan "right now" is for Ryan Fitzpatrick and Josh Rosen to both be on the Dolphins' roster for offseason workouts. Much of that is still in flux depending on whether Fitzpatrick, 37, returns for his 16th season and if the Dolphins want to invest in Rosen.

The most likely scenario is Fitzpatrick, the veteran gunslinger coming off a solid 2019 season who admits that retirement would be harder than playing football, returns for the 2020 season. He is under contract for $8 million with half of it guaranteed, and could start until a rookie quarterback is ready to take his place.

A Fitzpatrick and Tagovailoa combination for 2020 could be a wise route for the Dolphins.

Rosen's future is more murky as he spent the final 11 games of the season on the bench because Fitzpatrick outplayed him. The Dolphins appear set to give Rosen another offseason to develop under new offensive coordinator Chan Gailey, but an offseason trade can't be ruled out either.

Grier recently defended the move to acquire Rosen via trade, saying, "we'll always take chances if we think it makes sense for us to try and improve the roster."

The deal hasn't been a success thus far.

How do the Dolphins repair issues with their lines?

Coach Brian Flores cautioned that it could take multiple offseasons to rebuild the trenches and smart fiscal decisions will be made.

"Everyone thinks we've got all of this money to spend and blow. We're going to be judicious and responsible with our salary cap," Flores said.

Miami finished last in sacks (23), tied for last in sacks allowed (58), last in rushing yards per game (72.2) and 27th in rushing defense (135.4 rushing yards allowed per game). No matter who the Dolphins add at quarterback, their rebuild won't see success until there are significant upgrades in the trenches.

During the first week of free agency, the Dolphins should add at least two bonafide starters, and possibly more, to their offensive and defensive lines. They should double-dip during the draft too, by using at least two of their five picks in the top-60 selections on linemen.

Potential O-line free agents whom the Dolphins should pursue include Washington three-time Pro Bowl guard Brandon Scherff, Patriots ironman guard Joe Thuney, Titans offensive tackle Jack Conklin and Seahawks offensive tackle George Fant.

Some free-agent fits along the defensive front could include Jaguars defensive end Yannick Ngakoue, Patriots defensive end Kyle Van Noy, Bills defensive end Shaq Lawson and Ravens outside linebacker Matthew Judon.

Can Grier be trusted to nail this draft?

Grier might be the draft's most important decision-maker; the Dolphins hold the most and highest-value draft picks.

Like every general manager, Grier has a collection of hits and misses. Hits include cornerback Xavien Howard (2016 second-round pick) and linebacker Jerome Baker (2018 third-round pick). Misses include defensive end Charles Harris (2017 first-round pick) and Cordrea Tankersley (2017 third-round pick). Then of course, there's the success of Laremy Tunsil and Minkah Fitzpatrick -- first-round picks in 2016 and 2018, respectively, whom Grier traded away this summer.

Whether to trust Grier to nail the draft is a worthwhile question, but what should give Dolphins fans confidence is that he has a stronger scouting support system than ever before. Assistant general manager Marvin Allen and senior personnel executive Reggie McKenzie are respected talent evaluators who should increase the Dolphins' chances to hit on those picks. Flores, who began his career as a scout and enjoys that aspect of the business, will be heavily involved in the draft process.

Having many smart minds positioned in the draft room is a reason for optimism.

How will Gailey improve the Dolphins' offense?

The somewhat surprising firing of offensive coordinator Chad O'Shea after one season and the hiring of Gailey out of retirement means we will see a new Dolphins offense in 2020.

Gailey has a history of running a spread offense, and the Dolphins will likely implement more of that in 2020. But that doesn't mean strictly pass-happy. Gailey has led successful run offenses and he will try to establish that approach in Miami.

Some players described the Dolphins' offense under O'Shea as complex. The expectation under Gailey will be to run an offense that is easier to understand, which should help mold a young roster that will most likely include a rookie quarterback. Developing Rosen is on that to-do list as well.

Gailey's arrival is a big positive for Fitzpatrick, who played for the veteran coach in Buffalo as well as with the New York Jets. The reunion helps Fitzpatrick's chances to return in 2020 as the incumbent starting quarterback.