I have been running a single large TFT campaign since 1980. We quickly decided we didn't like the "Uber-smart barbarian" tendencies of the cannonical skill-acquisition rules. I developed a point-based decoupling from IQ that we have used successfully for 38 years, now.
First, at build-time, each character receives a fixed amount of points (depends on the game/campaign, but 50 points works well for "low-level" characters, and 60 points for "heroic" characters; 75 points is "epic", and 100 points is "mythic" - and very probably too unbalanced for most games). All attributes cost 1 point per attribute-point (just like normal). There generally has to be a pretty good backstory to justify attributes over 20 (Olympic-grade athletes), and attributes of 30 or more are definitely world-beating.
Skills and spells are bought just like attributes, using the official "cost". Thus, Polearms cost 2 build-points for a non-wizard, or 4 build-points for a wizard. Spells are bought just like skills, but wizards pay 1 per spell, and non-wizards pay 3 per spell. Skills and Spells must still be within the IQ capabilities of the character to be useble (and a pretty convincing backstory would be required to possess skills/spells the character doesn't currently have the IQ for).
In play, Attributes are purchased for experience, according to a variant of the "official" tables as amended by the Fantasy Master's Codex (©1981 by Metagaming), based on the current attribute-points:
<08......XP:25
<16......XP:50
<24......XP:75
<32......XP:100
<37......XP:125
<41......XP:250
<46......XP:1,000
<51......XP:3,000
<56......XP:5,000
<+5......XP:5,000*2^UP((<current points>-50)/5)
Where UP() means "round up to the next integer value". This gives a power-sequence for totals above 60: 10K, 20K, 40K, 80K, etc.
New Skills (and spells) have a cost based on current total-knowledge (KNO) divided by IQ:
XP = Cost*100*5^INT(KNO/IQ)
This means the Experience-Cost of new skills/spells is equal to the cannonical "point-cost", times 100, further multiplied by a factor of 5 for each multiple of the character's current IQ that known skills total.
Thus, Alchemy has a base Experience-Cost of 3*100 = 300 points if your total skills are currently less than or equal to your IQ. Up to 2*IQ, the cost would be 3*100*5 = 1,500; Up to 3*IQ, the cost is 3*100*25 = 7,500; etc.
This means IQ and skills are still loosely-coupled, but does not typically result in "Einstein the Barbarian" in 35 years of playtesting.
We also have a system for "Skill-Levels", that encourages specialization. That is a little more complicated (not much, but would take another post to explain). Levels work very well for weapon-skills and most spells. We don't currently have level-effects for most non-combat skills or several "Special" spells.
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I am signing up to run three demo-sessions of using these modifications to In the Labyrinth (original rules - hopefully still compatible with the rewrite) at TsunamiCon (
http://www.tsunamicon.org/gaming-and...d-information/), in Wichita, just after the SJ-Games Melee/Wizard demos. These will consist of both explanation and question-and-answer about the modifications, as well as the advantages (and very few limitations) of using this rulesystem for long-running Campaign games, and a moderately-long introductory scenario in my current (35 year old) gameworld. Characters will be provided if you want, but part of the session is intended to show how to use my "house rules" to quickly build your own characters. Currently, I am limiting these to 6 players per session, but interested non-players are welcome to participate in the discussions (and watch the games, if that floats your boat).