Years ago, I ran a Third Edition Dungeons & Dragons play-by-post game. One of my players asked to play a ‘blue mage’ that was developed by (if I remember correctly) another member of the forum but I didn’t like the class and wanted a chance to offer him an alternative. He ultimately refused the class I made and I caved.
I found my magician class and I’ve uploaded it. It isn’t for everyone, particularly not ‘character optimizers,’ but it covers a lot areas not normally found in a single arcane class. They combine medium skill selection with a medium attack bonus, light armor (via armored mage analogue) and simple weapons.
In addition to the above, the magician gains the ability to use Detect Magic as an at-will spell-like ability, and has the option to take on a familiar. Their primary “schtick” is their Spell Repertoire ability, which allows them to duplicate the effects of any spell they observe and successfully identify with a Spellcraft check.
They gain the ability to duplicate the effects of spells of successively higher levels (basically character level divided by two), 2nd-level spells at fourth, 3rd-level spells at sixth, 4th-level spells at eighth, and so forth. They gain the ability to learn and cast their own spells, but only up to 6th-level (much like bards).
When they use their Spell Repertoire ability to duplicate an identified spell effect, they expend a number of spell slots that total the spell they’re duplicating. In other words, once they’re 18th level, they can use like, three 3rd-level slots to cast a 9th-level spell. If you do the math, they can throw around more 9th-level effects than a sorcerer.
Oh, and these are cast as ‘spell-like abilities,’ which means they don’t need spell components. The main drawbacks are twofold: each ‘improvised’ spell requires a full round to cast (thus they can’t be readied or used to counterspell), and the character must of course observe and identify the spell effect in question.
There is technically no limit to the number of spell effects a magician can memorize, and I left it deliberately vague so the game master could decide, should they think it necessary to rein in a magician’s power. The magician gains a unique variation of ‘evasion,’ and the ‘mettle’ ability, which is rarely seen outside of… anywhere?
Finally, the magician gains the Timeless Body later in their career, and their capstone ability transforms them into a native Outsider and they gain Spell Resistance. The idea was to create a more balanced arcane caster, something comparable to say, the bard.