Mascal, welcome back buddy...
SL is solid as a wall of titanium !!
Except when you dont have a rock solid install... As I mess with audio, SL complains a bit. appart from that tampering, I can't rememeber it ever having a hick-up, a stall, a crash, a KP, whatever!
1 - Sure, use the retail dmg and restore to USB stick, pre formatted to HFS+J and GUID.
2 - Before restoring, yes
3 - Install Chameleon onto pen drive, the got to pen root and delete "Extra" folder and Boot.ini (I put and app for this in my SL tutorial download files)
4 - Copy my provided USB Extra folder to USB
5 - Copy "boot.ini" to USB...
6 - Not sure it it is really really necessary for boot, but I did it anyways because its real quick and you only have to do it once for that USB stick, which is to fixate the USB's UUID to the three file, sbios.plist, com.apple.boot.plist and PlatformUUID.kext
Then reboot, f12 or ESQ or whatever brings up your "preffered boot menu" or go into BIOS and put USB first... and ther you go!