I disagree. This is a valid approach to RPG design. It is the one 4E took and successfully achieved. But it isn't the only consideration when designing an RPG. Many gamers prefer the possibility of sub optimal choices, because they want their character creation choices to matter and have an impact on the power level in the game. This isn't for everyone. But it doesn't mean the presence of sub optimal choices in a game, mean its a design flaw. Different games take different approaches, and have different levels of balance. That doesn't mean 3E is a bad game, because wizards can become very powerful. And for many, the ability of wizards to bend space and time, is very important to having a fun adventure. Even for those of us that prefer fighters. We want the spellcraft that surrounds us, both at the player and NPC level, to have this kind of power.
Effectively then, the game becomes about one class then.
In Revised d20 Star Wars (pre Saga), there were 9 classes; 6 non-Force using classes (soldier, scoundrel, scout, noble, fringer, tech-specialist*) and three Force-using classes (Jedi Guardian, Jedi Consular, Force Adept). In theory, each class had a niche in the Universe be it combat, skills, social ability, survival skills, crafting, or Force use.
In reality, there was really two classes: Jedi Guardian and Jedi Consular. (Force Adept pulls a distant 3rd, the other six don't even register, though solider was the best of the last six). A Jedi (either one, actually) could out-fight a fighter (lightsabers deal a ridiculous amount of damage, ignore armor, and deflect lazer-beams. Plus, they were three-feats from the best AC in the game), consulars had every diplomatic trick a noble could pull (save for cash) and with a few spread ranks, a Jedi could pilot, camp in the wilderness, build a weapon, and do anything the other classes could.
Oh yeah, and he had The Force. He was the only class to Heal, Buff, Move at great speed, Read Minds, See the Future, Talk Long Distances without Tech, Move Objects, and (if darkly inclined) attack for stupid amounts of damage at range, followed by igniting his lightsaber.
Smart players (meaning, anyone who played for more than 5 sessions with a Jedi PC) knew the Jedi WAS the game. As PCs died and or were early retired (both common in Revised SW) Jedi replaced them. In fact, barring a few corner-cases, there was NO reason NOT to be a Jedi, since you stood head-and-shoulders over non-Force uses to the point a non-Force User was simply a liability or often treated like a sidekick (making them almost PC cohorts).
Canonically, this fits the SW universe. Luke was as good a pilot as Han, a strong a warrior as Chewie, and as competent a diplomat as Leia (ask Jabba about Luke's negotiation skills) AND could stand toe-to-toe with Vader, something Han, Leia and Chewie all failed at (together!) Jedi ARE supposed to be better than normal people in the SW universe, that's why they're held in awe and suspicion.
But that makes for lousy party dynamics, esp if your the guy whose playing Han, Leia or Chewie. (For the record, Han & co. only shine when Luke is off at Dagobah or on DS2 in Empire and Jedi, when he multiclasses from mundane to Jedi).
Saga fixes the problem (somewhat) by giving those non-Force classes something interesting to do. A solider now matches a Jedi in damage output, a scoundrel has many more skills than a Jedi could hope for. A noble is the only class capable of buffing. Jedi have weaker skills, less combat prowess, but still the Force to balance it out. They are still stronger than a non Force, but No longer the Black Hole of Awesome that sucks away the spotlight from anyone less awesome then them (which was, of course, eveyone else).
Is it as true to the tone of Star Wars as Revised was? Who cares! Jedi needed a power-crippling and the non-Force classes needed a boost to make the game fun.
Its always ok to blow off "balance" when your not the class being drowned out of the light.
* I never, ever saw a Tech-Spec in play. They were the true "sub-optimal choice" of the game. Weak HD, poor attack and saves, not even proficient in a pistol, but they could craft masterwork gear! Woo Hoo! Why was this a PC class when you couldn't contribute anything of value outside your garage?