Kingston has 2 lines, and if there import goalie panes out just need to look at shoring up a third line, I don't think their defense is particularly strong, and they don't have an abundance of picks so it would be a clearing house exercise if they were going to contend. Barrie has three lines but no goaltending, if they try to use Greaves they will need to make an OA available, which weakens there top 2 lines for what is a very mediocre goalie. Barrie has enough picks to do whatever they want as long as the players are available to make them better. Hamilton has three good forward lines, but isn't particularly strong on defense or in net; with minimal picks to work with they could try to flip a forward for a D. I wouldn't lose track of North Bay this year either, they have 9-19yo returning, no elite scorers but well balanced across the team, plus 3 OA forwards, there picks have been very high the last few years so they project very well in a supporting role.
Ottawa as has been noted before has three good lines but no definitive top scoring line; they have open OA positions but not an abundance of picks to work with. They also have a number of unproven 17 & 18 year olds who were selected high in the draft including Moldenhauer to work into a trade. I don't see Ottawa as a top 3 team in the east without making some transactions BUT no one thought they were that good going into the 18/19 season and they ended up in the OHL Finals, and in 19/20 there were a lot of questions about who would replace the scoring and they were the top team in the Country at the time of the shutdown.