With a 4 piece band, I'd look at a digital mixer - you have far more control with parametric EQ and dynamics on each channel as well as on the mains and monitor outs. I went from early on using a Mackie 1202, then a 1402, then a 1642, and then had a Yamaha 01v - the digital EQ on each channel was a game changer, but the mixer is pretty massive. Bought a B-stock DL1608 and have been very happy. Mackie just released new software that can be used on iOS, Android, and even Mac/PC. Worth taking a look at used.