The "cliff's notes" version of what you need to know:
1) Cross-drilled rotors are for style only. They will not work better than solid rotors in any situation that your LS430 will ever see. Remember, your brake rotors are basically just heat-sinks which means drilling holes in them reduces the capacity for that rotor to store heat. Despite the marketing you read, a drilled rotor will not dissipate heat any faster than a blank rotor. Slotting will shave your just pads like a cheese grater. In return, you will increase the initial bite of your pads. Your choice if this is important to you.
2) Braided steel covered teflon brake lines will improve the pedal feel and that's it. Your choice if this is important to you.
3) Brake Fluid: The best cheap fluid on the market, in my opinion, is ATE Superblue. The second best for cheap fluid is Valvoline SynPower. Both of which are rated at temperatures much higher than they are likely to see in your car.
4) Semi-metallic pads are organic pads with metal mixed into increase friction and raise the temperature range at which the pad operates. Typical ceramic pads are designed to reduced dusting compared to organic pads, but may not work as well as semi-metallic pads at higher temperatures. For the driving you will be doing in that car, high quality ceramic pads from a company like Hawk should suit you fine.
Hope this helps.
Adrian
