The storylines likely to dominate Formula One in 2019

Driver of the 2018 F1 season: Any rivals to champion Hamilton? (1:47)

ESPN's F1 team pick their standout driver of the 2018 Formula One season. (1:47)

Formula One has always been a sport of compelling narratives. Though new ones will emerge during the new season, there are several topics we know we will be talking about for much of the year -- we've outlined the biggest below.

Vettel versus Leclerc

Ferrari has set up a box-office partnership for 2019. Promoting junior starlet Charles Leclerc from Sauber after his impressive rookie season will put him alongside Sebastian Vettel, whose remarkable capitulation last year cost him and the team the championship.

Promoting Leclerc was hardly a ringing endorsement of Vettel, who wanted the team to continue with Kimi Raikkonen. Given how the four-time world champion crumbled under the pressure of Lewis Hamilton last year, it will be fascinating to see how he deals with a competitive teammate on the other side of the garage.

The German driver has previous experience in this scenario. Vettel was famously beaten by Daniel Ricciardo after the Australian's promotion to Red Bull in 2014, and it would do further damage to his legacy if he was unable to see off the challenge of the impressive but still inexperienced Leclerc this season. Add into that the huge pressure on Ferrari to avoid a third successive championship implosion and all the ingredients are in place for a fascinating season.

Six for Lewis and Mercedes?

It's difficult to look past Lewis Hamilton and Mercedes when making early predictions for 2019. Hamilton reached a phenomenal level of form last season as Vettel's challenge crumbled, seizing the initiative and never giving the Ferrari driver a chance to regain the momentum. If he can maintain that level into next season, it is going to take a lot to prevent him from winning a sixth title.

Doing so would put Hamilton on the cusp of equalling Michael Schumacher's tally of seven, while he is also closing in on the German's all-time win record. But it would also be momentous if his team was able to do the same. Another constructors' championship for Mercedes would see it equal Ferrari's run of six in a row, which it claimed between 1999 and 2004. That would give the current world champions a legitimate claim to be the greatest team in the sport's history, especially as it has maintained this run either side of the 2017 regulation revamp which was supposed to threaten its position at the top of the pecking order.

With all of that in mind, it is quite fitting that Ferrari appears to be the most viable team to stop Hamilton and Mercedes from edging closer to overwriting the records so closely associated with the team from Maranello.

More overtaking?

The "Blade Runner" prediction of having hover cars by 2019 was slightly optimistic, so we will have to make do instead with the small but potentially significant tweaks made to F1 cars for this year. It is hoped that the simplified front wings and wider, deeper rear wings we will see on this year's cars will increase overtaking opportunities during races by reducing the turbulent air behind cars.

If it works, a driver should find his car less badly affected while following a rival's vehicle this year, meaning it is easier to follow more closely while also not punishing his tyres and brakes as extremely as in previous years. F1 racing boss Ross Brawn has said simulations suggest there will be a tangible improvement this year, but teams remain skeptical -- we won't know for sure until the season starts.

Any improvement in overtaking will bolster Brawn and his aerodynamic team ahead of the major overhaul to cars slated for the 2021 season. If the changes do not work it will only fuel uncertainty around the next set of rules and whether F1 can deliver a car which allows consistently close wheel-to-wheel racing.

How competitive will Red Bull be with Honda?

Red Bull is embarking on an exciting project with Honda, who worked diligently in 2018 with Toro Rosso to make slow but steady progress on its much-maligned engine. The improvements of last season have raised expectations in the Red Bull camp, with Christian Horner claiming at the end of last year that Honda was already ahead of former engine partner Renault.

Red Bull has not had the power unit to challenge for a championship since the introduction of V-6 turbos ended its run of dominance at the beginning of the current decade. But it has lost none of its prowess in the aerodynamic department -- in previous seasons Red Bull has shown it can compete with Mercedes and Ferrari for occasional race wins despite a significant power disadvantage.

It remains to be seen whether Honda is ready to help sustain a challenge over 21 races. There is no doubting the fact that if it is a better engine than Renault, as Red Bull believes, it will be in tremendous shape. The team might have lost Daniel Ricciardo to the Renault factory team, but the prospect of the constantly improving Max Verstappen is hugely exciting and reason alone to tune in to the season opener in Australia on March 17.

Has Ricciardo made a terrible mistake?

Speaking of Ricciardo, he is likely to face a lot of questions about the form of Red Bull this year. The Australian's decision to switch to Renault's factory team is, right now, a step backwards from a team entering an exciting new era to one which is currently best of the distant midfield pack.

Renault is clearly making progress, but it's hard to see the team bridging the gap to the front in 2019. Ricciardo has consistently said he was looking at the team's long-term future and he's got himself in on the ground floor of a team determined to put itself back at the front end of the grid. The French manufacturer has one eye on the next set of regulation changes and appears to be the most viable candidate right now to turn the "top three" into a "top four" before 2021, but it still would be a major achievement in just two seasons.

Progress might be slow this year, and that situation might be made all the more painful if Red Bull's partnership with Honda lives up to the lofty expectations listed above. Ricciardo spent five years waiting for a Red Bull capable of winning a championship -- he might be left kicking himself if that's exactly what the team has with its new partner in 2019.

What if Fernando Alonso and McLaren win the Indy 500?

Opinion in the paddock is split over whether Fernando Alonso's departure from Formula One is a full-blown retirement or a temporary hiatus. If McLaren ever finds a remedy for its current situation, it is hard to see Alonso staying away, but company boss Zak Brown has downplayed the chances of that turnaround happening any time soon.

Alonso and McLaren will return to the Indy 500 this year. There are numerous reasons behind that decision: Alonso has grown disillusioned with F1 and needs to win the Indy 500 to complete motor racing's triple crown, which also includes Monaco and the Le Mans 24 Hours. McLaren is doing the event as it continues to weigh up the potential of a full-time entry to the IndyCar series in 2020.

Some have suggested a foray into North American open-wheel racing is the last thing McLaren needs while facing such a dismal situation in F1. Winning the famous oval race would be a huge achievement and likely a welcome distraction from its struggles of the recent past but might also fuel Brown's desire to increase the team's activities away from F1. It would also mean Alonso ticks off his major challenge away from the F1 grid and could well lead to him considering whether he left the championship prematurely. The coinciding form of McLaren's car this year will also weigh into this scenario. Watch this space.