I'm pretty sure it doesn't take 2 months to fix a simple issue.
Probably not. But they likely aren't working on this at all, because it is a minor bug that has zero impact on gameplay. It's not at all uncommon for minor cosmetic bugs in other games to go unfixed for months or even years.
Most lead developers will prioritize cosmetic-only bugs below every other bug that has actual gameplay impact. Its likely that this bug will be fixed and slipped into some patch at some point, but it's silly to think that this would be given priority over almost any other bug.
Whenever they fix a bug they create about 3 new bugs, so yes it adds up because they usually don't go back and fix the new bugs they created.
No, you're still wrong. For every bug you see them fix, they fix at least a half dozen you never knew about. That's just standard experience for software services like this. You think its true because you simply aren't paying attention and are cherry-picking your evidence. Compound that with confirmation bias and --presto!-- you come to your incorrect conclusion.
Each patch does create new bugs. That's the nature of continual releases. If you think that isn't normal, then I think you don't know much about software. Bugfixes rarely create new bugs. Most bugs come from new features interacting poorly with existing features. SWTOR has had its fair share of these over the last couple year, and the grand majority of them have been fixed. You just don't see it because most people simply don't pay enough attention to notice when something is working properly. They only see the times when its not.
and Sith assassin sucks. They only get 100 force. why would anyone want to play that class? its not very productive. They need atleast 200 force to be worth while.
... and so not only do you not understand development, but you don't understand game balance, either. Shadows and Assassins are the champions of burst damage. The only thing that limits their dominance is the fact that their burst period is short, limited largely by their force pool. If you doubled that, Shadows and Assassins would be able to sit behind a target and unleash 7 to 10 consecutive Shadow Strike/Mauls.
That would be... really, really bad for game balance. It's very silly to suggest that.