Okay... while I'm a long-time Oblivion player, and have been aware of the metagame (Without taking part in it).. I've always made characters that are 'intuitive' - I've always grabbed the skills my character uses all the time as Majors, for the starting boost and accelerated pace.

However, like everyone else who does so, the Leveling and Level Scaling has come around to bite me in the ass. Although I use Francesco's overhaul to take the sting off the leveling (And not make the game completely easy at low levels), I still level too fast for my tastes. I don't like the idea of "Efficient Leveling"... to that end, I got a mod that just hands out +5 Attribute modifiers, though I may switch to SPAM if I can't find an old point-buy instead (The original leveling system is atrocious, as are most "natural" leveling systems. I like my attributes determining my skills, not the other way around). I also like leveling up irregularly, instead of controlling it.

To that end, I'm thinking of making a character that grabs the "Nuisance to level" skills as majors, though almost all of them are 'uncontrollable'. The character intends to be a "Do everything generalist", without having to wait until the end game to branch out into secondary and tertiary . The build should be:
Race+six:

Female Khajiit (Because I'm Me), though this is largely irrelevant.

Birthsign:

The Mage, since it allows me to be a spellcaster when I feel like being one, without carrying the baggage the other birthsigns carry. Of course, by using Alchemy, I might be able to pull off an Atronach sign. Ultimately, The Mage gives more resources than the non-caster birthsigns, and more resources means more options and more power. How viable is The Apprentice? Would the greatly-expanded magicka pool be worth the weakness to magic? I don't think there are many mage enemies. On the other hand, getting magic resistance up is a pain.

Attributes:
Strength - Carrying loot, improving the rate of melee skill advancement, and offsetting the fact that Khajiit have the lowest Strength in the game. Also, Encumbrance is a resource, tying into wealth acquisition, loadout options, and even a few skills like Acrobatics.
Endurance - Ties into the philosophy of "More Resources = More Options and Power", governing Hit Points and Fatigue. And hit points are the most important resource in the game.

Major Skills:
Athletics - It levels slowly, even as a major. It's completely uncontrolled, but that's not a bad thing to me. Also, its perks give more options by keeping my stamina high in combat. Being able to run away better has its advantages as well.
Mysticism: It has very few niche spells, but making it a Major allows me to always have the Soul Trap spell as an available option, which is useful.
Mercantile - Another uncontrolled skill, I think it levels slowly even as a major, and gives me more general resources in the form of wealth. I'm concerned that it might level too fast if I spend too much time selling and buying stuff in town instead of killing stuff in the wilderness.
Block - This skill is important to survival, and seems to level slowly. I'm running with Deadly Reflex 6 which makes blocking harder.
Armorer - it levels somewhat slowly, and is important for keeping my gear in good condition! Having it as a major means I'll be able to repair magical gear sooner. It also saves me repair hammers.
Speechcraft - I'm torn on this one, because I like getting people to like me so it's prone to overleveling. However, I have a few mods that make getting high disposition with certain people appealing, especially early on. I may want to replace this with another magic school, such as Destruction or Restoration.
Acrobatics - Another skill I'm torn on, because it levels actively, and I love to jump around a lot. It also levels regardless of whether I'm in town or out, and it might be too much in conjunction with Athletics, causing me to level up just by moving around. I'm kind of tempted to replace it with an Armor skill, but in my last few games, Armor was my fastest-leveling ability.

On leveling up... I probably intend to keep my attributes nearly-even (I'm getting +5's across the board as long as I level a skill that uses it up!), but I might want to max out Endurance first. Should I invest in Luck and only boost two other attributes at a time?

And while this is in general... anyone know of a "Fast-exit" mod? I used to have one back in 2009, but can't find the tweak anymore. I'm sick of the game crashing and locking my computer up for a few moments every time I try to quit.

You don't need a Fast Exit mod, just use qqq in the console to force a fast quit to the desktop. This is what any mod would do.

I always avoided Athletics and Acrobatics as Majors simply because they level just going around in the world (I like to jump around a lot, a habit from Morrowind as you move faster in that game by jumping, plus I swim a lot and that tends to skyrocket Athletics)

Your on the right track to making Major skills you won't use often to slow down leveling. You can also go against the Efficient Leveling plan and pick skills that fall into one or two Attributes.

However, the best way to slow down leveling is to just never sleep so you never level up. Or, picking combat and defense skills that you don't use in the game like picking Blunt if you swing a Sword. Making sure your most used skills are set as Minors or, better, Misc, will slow down the leveling from your main skills.

Just a thought on armorer. In your situation, I would find myself using it alot (even repairing the armor of my dead foes) just for practice because I would want it high for the perks. This would certainly speed my leveling up. As an alternative, you might consider marksman, which is extremely slow to level even as a primary killing skill, much less as simply a ranged 'introduction' to a fight. Another possibility is restoration, which also levels very slowly. Resto can be further slowed as desired by augmenting your healing with potions as necessary.

I use Fast2exit in Oblivion to avoid CTD on exit. I also use Realistic Leveling so I no longer have to worry about leveling issues.