My guess is that all the Life Day items will come in Cartel Packs and that will be the only way to get them. You could always trade for them on the GTM.
Because with that their employees wouldn't be able to work on any issues that arise from the patch, which is what they will be doing the majority of the time after patches.
The fact that they have to see what will sell first and what won't. Really, it's basic marketing. Like there would be no reason for them to spend a ton of time and resources on cool new armors if it turned out nobody wanted armors from the Cartel Market.
Code, especially for games, gets quite complicated with everything going on. Hard to really explain it to someone who hasn't had a few courses in coding, but just know that these things can be related even if they don't seem like they are.
Honestly I think the best way to play SA is to go with this spec: http://www.torhead.com/skill-calc#200bcrskrskbsZZf0cM.1 It makes you able to tank in both PvE and PvP. Also, you should gear dps with that, so prioritize Willpower over Endurance. With that spec and the dps gear you'll be able to tank pretty well as well as have a pretty good damage output.