Take this with as much seasoning as you feel appropriate, but YouTuber FP1Will had drinks with a friend who is well-placed within Aston Martin F1 and he related the following:
Newey has transformed Aston's technical department. Newey proclaimed that the gearbox needed to be shortened by 80mm (3 inches). When told it was not possible, he hand-drew said new gearbox in under two hours. Lawrence Stroll also verbally pissed on everyone's parade at the Christmas Party, telling them that for the money he has spent, the team has failed miserably. And, to nobody's surprise, the entire staff hate Lance and every year hope the rumors he is leaving come true.
In terms of engine development, AMG is in first place, with Honda and Ferrari close behind. Red Bull-Ford is a fair bit farther back and Audi's engine is effectively unusable.
He also said that Cadillac will likely not turn a lap during winter practice as their Silverstone aero department only has 40 people. The team is offering massive recruitment bonuses to try and poach aero staff from other teams.
I'll wager Honda is allot closer to AMG than Ferrari. I hope AMR has a competitive chassis.