Heck, I've run low magic games a number of ways.
1. Limit the magic items (and no magic shops)
2. Limit to all martial classes only - rogue, monk, fighter, cavalier, samurai, barbarian.
3. Limit to half casters and martials only - rogue, monk, fighter, paladin, bard, ranger, paladin, cavalier, samurai, ninja, barbarian.
4. Allow alchemist, magus, witch, oracle - no clerics, nor sorcerers and wizards.
5. E6/E8 - class levels only go to 6th or 8th, with skill points and feats increases only after that.
6. Run a game where use of magic is possible, but causes corruption, eventually forcing PC spellcasters to become NPCs. - such as
xoth.net setting
With each of these options, managing the CR of your opponents is still necessary, though amount varies with each limitation. You have to play it by ear.