There are enough batsmen in the tank. Sanga, Mahela and Dilshan will play for another four seasons. Samaraweera one or two.
Mathews is obviously going to be the main batsman, good enough to average 50 in the tests.
Kaushal Silva, Dinesh Chandimal (keeper batsmen), Kandamby and few young players are promising with the bat. Fast bowling has enough bench strength with Malinga, Fernado, Thushara, Kulasekara, Prasad, Welagedara, Perera and Mathews. Spinners are plenty possibly best period for SL spinners with Mendis, Randiv, Herath, Senanayake and Prasanna. All are very different, (unothadox ones, Mendis, Prasanna, orthadox ones, Herath, Senanayake and inbetween ones), and excel at different conditions as well.
SL is going to emerge as a force, because their bowling is getting to new heights.