No you don't have to drill the pistons, however I am starting to play with some smaller holed pistons with a little lighter oil.
AE big shock pistons fit perfect and in a pack you get 4 1.3 pistons and 4 pistons with dimples for drilling 6 or 10 holes. Luther mentioned Jammin pistons but they cost over twice as much and they don't have the blanks. If you want to play with pistons I would get 2 packs of AE big pistons and drill away if the 1.3s aren't good.
Here is a little chart I made for total hole area on 6 and 10 hole pistons.
10x1.0mm = 7.857mm2
10x1.1mm = 9.507mm2
6x1.3mm = 7.967mm2
6x1.4mm = 9.240mm2
I am not totally sure on this however the 10 hole pistons at 1.1mm should have similar static feel as 1.4x6 but the smaller holes should have more pack. I am going to play around with this for a while soon.
On another note, I was putting together some new rear shocks last night and when you crank down the seal cap it seemed like the seals were too tight. If this happens, I ended up sanding the little white seal from 1.1mm to 1.0mm. On the black bottom piece I took this from 2.6mm to 2.3mm grinding only the big side which faces the seals. After this I lubed up the seals, re-inserted the shaft, and it was much better.