Giovinazzi is an interesting case and could turn out to be more crucial for the driver market than we think.
Assuming the 2nd Alfa is reserved to one of the new Ferrari rookies the 1st seat is between him, Kimi and outsiders (Hulk for example, Vasseur rates him). since Vasseur wanted him out this year he needs a massive improvement next year.
But even if he gets dropped, he ticks off the Haas requirement of being relatively experienced, and the team has Ferrari ties.
Now let's go even further: What if Giovinazzi does improve massively? He's Italian and there were indications that Ferrari wants a #1-#2 policy again. If (and big if) he does manage to improve much I wouldnt rule out this scenario. In 2004 Felipe Massa didnt look like a future Ferrari driver either.
I was actually thinking this the other day, Giovinazzi has been quietly improving (at least in qualifying, matching and beating Kimi) since the summer break. Be interesting to see how he does next year, a genuine improvement, beats Raikkonen, Vettel leaves at the end of 2020? Italian Ferrari driver alongside Charles?