my group allways used weapon and casting speeds, but most people I played with tended to stick to one or two weapons making there init easy to figure out, I was often a mage but I tend to decide what spell I am casting well in advance of my next turn.
weapon and casting speeds helped some character concepts, the big slow two handed weapon was actually slow, the dagger fighter tended to go early in the fight. Some spells benefited from it too, the power word spells where impressive due to there init 1, where as most spells had an init equal to there level. Adding 1 instead of 9 is what made power word kill despite its other weaknesses a valuable spell, a status it lost in the later editions where it was just a very high level death spell.