By 1985 I was looking for alternatives to ADnD 1st edition. The game that inspired me to make the break was Fantasy Hero. Like most of the hero system games, it was a complete standalone RPG. By the late 80s the Hero System adopted the same format as GURPs and other generic system by having a central core book and then follow on sourcebook detailing a genre or setting.
At first a fan of this (for both GURPS and Hero System), around 2000 I felt it to be a huge detriment. The core + supplement was very convenient to use as a reference, but failed miserably in helping my friend learn or to adopt the game. The buy-in was too great.
This is in contrast to Chaosium and Basic Roleplaying which maintained a series of standalone RPGs while still putting out the occasional supplement that supported the entire line.
GURPS still has this issue but Hero Games has decided to return to the older format. At first with Champions Complete, and now with Fantasy Hero Complete. They have launched a kickstarter to get the book published.
Fantasy Hero has the typical mechanics that most skill based systems have. Skills, Characteristics, Talents, Disadvantages, etc. Like GURPS they are setup through the points you get at character creations. What makes Fantasy Hero shine is the use of the Champions power system for spells and magic items. The amazing flexibility of this allows referees to define campaigns with radically different magic systems. If you are crazy enough you can even have a campaign with multiple magic systems. Thanks to the powers framework you can see how they relate to each other.
Here is a link to a review of First Edition Fantasy Hero.