With regard to the striker: What Mike said. If you run a reduced power firing pin spring, you need to run a lightened firing pin(I was corrected at the glock armorers class last month when I called it a striker - go figure) to get reliable ignition on CCI and winchester primers. I personally like the combination. It can make your trigger pull a little bit mushy, but I like to go as light as I can. I don't use the titanium part, just the lightened stainless steel model from Lightning Strike with a 4# wolff firing pin spring. I get reliable ignition with all primers except wolf, and I like the trigger pull it yields.
I'm going to differ from the rest here about the safety plunger. I use an aftermarket one in both of my competition guns. I don't know if they're titanium or not. The main feature that I like about them is that the curve at the bottom is a smooth and rounded instead of being angled and flat like on the stock one. IMHO, if glock really wanted to create "Perfection" they would have rounded off the stock ones to be nice and smooth. You can shape and polish a stock part to work just as well. The improved shape of the plunger paired with the reduced power plunger spring they come with takes the last little bit of slop(I always think of it as the false wall. I hit the FP plunger thinking I've taken the slack out, only to squeeze the shot and have the trigger creep a bit longer before the shot actually breaks.) out of the trigger pull when you get to very low weight pulls.
All that said, if you really want a better trigger pull just save your money and take it to Mike from the beginning. Trying out different parts only to realize you don't like them or that they negatively affect reliability, then having to order different parts and lose matches because you have jams, etc is a huge pain in the ass that costs way more time and money than a professional trigger job from someone reputable like Accurate Iron. If I could do it over, I would have had Mike do my trigger and I would have some money in my pocket instead of a box of extra parts that didn't work out.