Agree on Severna Park and South River. Severna Park will have a potent offense with Alex Ramsay, Brent Jones, Dave Turner (hopefully healthy all season) among a deep team of hitters. If they can get decent pitching they will do well. South River has some good returning talent as well. Aumann, Hite, Loftis are are some of the counties best.
Also agree to not discount Arundel. Bernie has a good nucleus coming back and he really does get the most out of his players. He cares about all of them and they play hard to reflect this. They are well coached and are fundamentally solid every year.
Old Mill has several returning players and should contend as well. They have the talent to win the county and we will see how they respond to their new coach, Jeff Martin, and his "system" as Mel Montgomery has retired.
Anne Arundel County should be interesting this year as there are several teams, including some that Have not been mentioned in these posts, with good pitchers who could make things difficult for even the projected "best" teams.