Dreamteam67: I hope someone has played through BG sometime with a character having 3's, 7's and 9's for relevant stats, just to prove how wrong you guys are about "needing" perfect 18's.
Define "relevant"; if you are talking about prime requisites or other minimums required for a class, then that is a monumentally awful idea, if I am understanding your proposal correctly (3/7/9 for each stat equal to the minimum needed for a class). Let's take a look at what would happen if that were to apply to a mage:
3 Strength: -3 to hit, -1 damage, 5 pounds carry weight. The combat modifiers don't seem like that big of a deal until you realize that even a mage needs to be able to defend themselves if they get backed into a corner. The weight cap is so hilariously awful that I'd be surprised if you could even hold a weapon to begin with.
3 Dexterity: -3 reaction adjustment, -3 missile to hit, +4 penalty to AC. Now the mage can't even use a sling reliably, and before their abysmal reaction adjustment lets them act in a round, the first ranged attacker that fires a shot at them will hit them reliably.
3 Constitution: -2 penalty to each hit die. Because of this, the aforementioned hit will kill a low level mage; sure, there might be spells and items that raise each stat, but that's all moot if the character can't survive.
9 Intelligence: Can't learn level 5 or higher spells, 35% chance of learning a spell. This one can be modified with items (again, assuming you love long enough to get them), and the level cap makes it so that at most the player is missing out on just level 5 spells in BG1. Carrying that character over to BG2, wherein you have lost all your magic items, would be another story.
3 Wisdom: -3 penalty to all saves. This makes a mage level 1-5 go from a ~40% chance of making a throw against spells to 22.23%. If the arrows didn't kill you, then spells will. (Or not; I can't determine if this was actually implemented in the game despite being mentioned in the manual)
3 Charisma: makes it almost impossible to get along with any of the NPCs, but that can be remedied by having Imoen be the party leader.
Either way, BG starts the PC at level 1; in AD&D language, that's the DM saying that they don't like your character concepts and that they expect something more interesting from everyone after a TPK. I do love rolling dice for my character, and I do not ordinarily mind having abilities that don't grant beneficial modifiers, but since BG doesn't make my ability scores really matter most of the time unless it grants me a modifier in combat (as opposed to rolling against attributes for various non-combat skills, which is how 2E made stats actually matter even when they didn't grant modifiers), high stats early on are almost essential given the odds of dying in the game before factoring in the ways that the pathfinding AI will get you killed.