sage_for people not invested in ozfortress this roster is ridiculously stacked.
If you were (and people will inevitably) compare them to Jasmine they are potentially a much more solid roster. In terms of scout combo, roamer and medic I'd argue straight upgrades. Sam and lams(cooki) are about as scary a combo of scouts can be; Sam is plain and simple the best aimer I've seen in TF2 period. Doge is individually one of the smartest and most mechanically skilled people I've ever played with. riot is unfair, he's like an anime character I don't get how but his power just scales to always be on other level of the people surrounding him, Australia hasn't got a reputation for fantastic roamers but riot has broken that curse.
In terms of demo and medic you couldn't find better replacements for geoh and Paulsen then with yewl and redcoat, redcoat is the only person who could contend with Paulsen for his strengths in maincalling and aggressive strategy, and whereas geoh had some of the best aim and dm in the country yewl is a super selfless player who's mindset lies solely in what his play can do to make his team's job easier.
Geoh and Paulsen are my favourite demo and med mains