Upgrading a shocker is personal perference. There is not need to improve the trigger if you are firing fast anyway, better concentrate on other aspects.
One of the first upgrades I would suggest is get a decent barrel system. I used a Freak on my shockers, and they were awesome. Well worth the money, and I am using the same Freak kit on my LCD Matrix now, just with a different back. If you wanna upgrade the trigger, make sure you have the new style LS board. It can take the blade triggers and is sweet, or for the same amount of cash (board + trigger = I-Frame) get an I-Frame from wither hypersports works, or Smartparts Europe. They make the gun much easier to fire, and give the shocker a more natural feel.
If you are running on CO2, then a shocker filter is probabily a good buy too. It will keep the firing system clean as the dirt you get off using CO2 is unbelieveable! They are about £20-25 last time I checked, from either Planet, or Smartparts.
If you need any more advice, just mail me at
andy_c182@yahoo.co.uk and I will be happy to help.