[Alacrity]

Alacrity is fine, having to grind crit/surge mods is just grey hairs waiting to happen.

 

Change your skill tree to include combat stims (lethality) http://www.torhead.com/skill-calc#401MffbzGoRzcZZGbbkM.1

 

Use diagnostic scan in your rotation, enjoy stress free HM boss fights.

[What's the pros and cons between Lethality Operative VS Lethality Sniper?]

What is TA?

 

Tactical Advantage. It's a temporary buff applied by some Operative skills and consumed by others.