So, any discussion of stats is more complicated than a quick answer can address. Crit and Surge have a very clear link so that getting more of one makes the other better too but actually every stat has this relationship with every other stat to some degree meaning that if you stack Crit and Surge and had very low Alacrity you would find that a point of Alacrity would be worth far more than if you stack lots of Alacrity. Almost every stat (Alacrity, Crit and Surge specifically for us) also has an enforced diminishing return in ToR meaning that the closer you get to a point decided by BioWare the less each rating point provides.
So, it's complicated.
Fair enough but you need some advice on how to gear right?
Kor - over at SithWarrior said:
Crit between 250 and 350
Surge between 200 and 300
Alacrity between 100 and 200
Power as high as possible given the above (preferably no lower than 300)
Willpower as high as possible
And this is a really good and relatively simple guide to follow.
Essentially, Willpower and Power are VERY strong and don't suffer diminishing returns so they should always be taken when available. Surge is still pretty good after it got nerfed but hits diminishing returns quite quickly. Alacrity, kinda sucks to be honest and using PvE gear you'll want to be swapping out enhancements in your gear to try and off load some of the massive amount that BioWare has given us. If there are spare tokens available from raids or FPs look out for Imperial Agent head and glove tokens because those items have Power/Surge enhancements in that are really good for us.
Hope that's helped. I'm sorry it's not as simple as just giving a straight answer but I would be wary of anyone that does try to give a straight answer on a question like this. Theorycrafting tools are getting better (SimCraft for Sorcs is already a really strong tool!) but they still can't get round the fact that each stat's worth depends so greatly on all the other stats.