The color crystals being sold on the Cartel Market in SWTOR are for all intents and purposes purely for looks. Sure they do give players access to the currently maximum level stats for a color crystal at level 10, when normally said crystal is not available until level 50+. But if a color crystal makes or breaks anyone in SWTOR, they should reconsider playing the game to begin with.
The other Cartel Market items are cosmetic items, speeders, XP boosts, and unlocks that F2P players can purchase if they so choose to get access to things without having to pay a continual subscription fee. Now, some of the cosmetic armor sets are "fully functional" and are all modded out, so players can just equip them and go. But 99% of the Cartel armor sets are just "skeletons" and for customizing your characters' looks.
I've been a SWTOR subscriber since the game's release, and while yes I've done my share of grumbling and griping about Bioware's inability to fix this bug or that...or having "fixed" bugs reappear. But overall I've enjoyed the game experience, and despite what this person or that person may say...how an individual is going to judge the class stories is up to that individual.
In the grand scheme, it is a game for those who enjoy Star Wars and want to watch lightsabers clash and blaster fire wizz by their characters. I also believe players would get more out of the game, especially first time players if they took the time to watch the quest cinematics. Having seen them at least once, makes me smile every time I go through some of the repeatable quests, knowing what's going to happen next.