There are many questions surrounding Essendon ahead of its 2020 campaign.

How will the coaching succession plan work? Will they be able to assemble a midfield that bats deep enough to match it with the best? How will an injury-affected off-season impact? Can they find the consistency required to be a top team? 

But a crucial one lays in arguably football's most basic principle: can they kick enough goals to truly be a top-four threat?

Essendon's scoring fell to an average of 77 points a game last year, compared to 88 in 2018 and 95 in 2017, when it made the finals and spearhead Joe Daniher was an All-Australian key forward. 

Scoring competition-wide fell last season, but Essendon’s dip was more pronounced as it has tried to become a more defensive unit.

As has been well documented, Daniher has had a slow rehabilitation program from his groin surgery last year, as the club remains extra cautious with his recovery.

So the Bombers may again need to work out ways to compete with the top teams without Daniher, should he have a delayed start to the season.

Daniher wasn't the only forward to miss chunks of last season through injury, with Orazio Fantasia, Devon Smith, Shaun McKernan and James Stewart also facing lengthy absences that made the starting forward six a rotating mix of faces every week.

Plenty was left to Jake Stringer, who has been an excellent recruit and won the club's goalkicking in both of his years at Essendon, and small forward Anthony McDonald-Tipungwuti, an extremely durable and robust goalkicker. 

The good news is that Fantasia and Smith are back up and going and completing all drills at training. Fantasia looks sharp, quick, agile and hungry, and Smith's fierce tackling and pacy movements are back.

But the key-forward stocks are still a challenge, with Mitch Brown delisted at the end of last season and Stewart still on modified training as he manages his own groin issues.

The options aren't endless for coach John Worsfold and his 2021 successor Ben Rutten. But could the emergence of a young defender force their hand?

Over the past 18 months, there has been interest in the development of key back Brandon Zerk-Thatcher, who made his senior debut in against Fremantle in round 22 last year.

That night, the now 21-year-old was a late replacement for veteran defender Cale Hooker.

But if Zerk-Thatcher's marking prowess, agility and game sense continue to take shape and force him into the Bombers' backline, could it make for a more permanent role change for Hooker?

The Bombers' backline can't fit all of Hooker, Michael Hurley, Zerk-Thatcher and Patrick Ambrose, let alone Aaron Francis who will be hoping 2020 is his breakout campaign across half-back.

Hooker has shown more than any of those that he is capable of making an impact in attack. Last year it was in cameo form, proving a match-winner with late goals against Greater Western Sydney and Gold Coast.

But in 2017 he kicked 41 goals from 20 games and was the perfect foil for Daniher, who booted 65 that season. Three years on, at 31 and after an injury-interrupted pre-season, he may not be capable of that same output, but if Zerk-Thatcher is barging down the door it will cause a restructure in the back half.

How the Bombers configure their talls – particularly with a lack of depth in that area in attack – will be fascinating, and crucial to their 2020 hopes.