Winning slams is what it is about, so I'd take Serena's year.
I don't get this bit you wrote
Lindsay and Maria started the year in a brilliant fashion and look to have the goods over all other players for the season.
How exactly do they have the goods over Kim? And she started her year later than they did.
Maria - three titles - one tier I, One tier II, one tier III
Lindsay - four titles - three tier II, one tier III
Kim - seven titles - one slam, three tier I, three tier II.
Justine - Four titles - one slam, two tier I, one tier II.
Edited to add Justine, she deserves to be there to