Every time , that I took the decision of buying an meter , I took it because I wanted something that was missing from my toolbox .
Examples :
An small portable
An True RMS
An all around portable ( capacitors - transistors tester - thermometer )
An heavy duty analog ( measures lots of Amperes - RF does not kills it - the needle can not be fooled )
An bench type DMM ( always ready for action - stable behavior - safe to use )
Or many bench type DMM ( multiple measurements - live comparisons - instant decisions of what behaves properly from the tested circuitry )
Thats my tips.