I think your main problem here is you are confusing "it's not super easy without this" with "essential".
No, I don't think I am. I don't want the game to be super easy. I just don't want to have a character that can only do a single thing. I want my character to be able to learn over time how to disarm mines, how to cut steaks out of animals, how to sneak, how to shoot, how to pick locks, and so on. It makes no sense whatsoever that a character that survives as many intense situations as a FO protagonist is a one-trick pony.
Really, I'm just asking solely to have some jack of all trades abilities. I want to be able to sneak past a mutant camp without getting spotted right away, not to move into the camp and slash half the guards to pieces with a chainsaw that nobody can hear and then pickpocket a grenade onto a nearby super mutie overlord. I want to be able to open reasonable locks, even if the top quality locks are beyond me. I want my gear to be of usable quality, even if I'm not a specialist in repairing them. I want to have a cursory knowledge of computers, even if I'm not 1337 hacker. I want to be able to talk and emphasize points like a normal person, even if I'm no diplomat. I want to be able to trade as if I actually have a brain, not constantly take my pants off and ask every vendor to have his way with my abused ass.
I'm no masochist, I just enjoy playing the game the way it was intended to be played. Games like Fallout are rooted in replay value and the joy of the road not traveled. Character creation is supposed to supplement this and create a unique and different experience from the last, god mode pretty much rips out the heart of the system and takes a pretty shameful piss on it
Who's asking for god-mode? FO3 was broken for a number of reasons. Part of it was the amount of health you'd end up with. If they'd taken out the level-up bonus to health then you could've gotten 300 health and that's it. With that amount of health, a lot of enemies would be dangerous even at level 30. Another issue was Almost Perfect. With AP in the game, anyone could simply max int, get to level 30, and have the best of both worlds. Easy. Without AP, players would've have to prioritize their SPECIALs.
Of course, that's another problem with FO3 balance. SPECIAL stats are nearly useless except for the perks they allow you to invest in, which meant that it didn't really cost you much to ignore agility and charisma until you could get Almost Perfect. Strength at 5 for Strong Back was fine as well. Not like you'd be sacrificing any perks, which means no reason to ever take it higher. Same issue with endurance. Starting value of 5 or 6 would have no cost in the long run.
Really, it wouldn't take all that much to make FO3 challenging even at level 30, even with maxed skills. That's not really what this topic is about, however. This topic is about how skilled characters will be in New Vegas, and I really hope that Obsidian isn't going to run head first into the other extreme and make characters that literally can only be masters of one thing or jacks of a few. It takes too much away from the exploration and adventure aspect of the gameplay.