Short answer is no because outside any single speaker rig will get pushed to it's limits. But that said the one non line array EV box that will get significantly louder than what you have and be a significant upgrade in terms of vocal projection is the QRX212. Yes that box outperforms the ETX12p which is also louder than the ELX12p but it's not a lot better with vocals, it's still just a single 12+1 box while the QRX is a dual 12 with a large format compression driver.
The QRx212/75 is a big step up as it also has a 3" horn. Our QRx rig with QRX dual 18's rents for three times what a speaker on a stick rents for. It is passive and needs an amp tank to rent with it. 4 Dual 18's and 4 tops is a substantial system. The 75 degree horns can be carefully splayed if you need wider horizontal coverage. The QRx subs have much great Xmax and power handling. We are feeding them with a 3kw amp and another 3db would be nice. You can use the Matrix in the M/X32 to cross them over (the PEQ settings are all over the web or I have them if you need them). All in all the QRx is a huge upgrade if your clients are going to pay for more.
WRT the EV tops, stop stacking them. That is going to cause destructive interference.
An upgrade would be the Yamaha DZR315. Nice powered 3 way box. Would give you another 4.5db of honest output. They sound great too. I am dumping my QSC 3 ways as we have fully depreciated them and we are shifting to all Yamaha for our SOS stuff. The Yamaha subs are really nice too.
If you go the Yammie path call Mike Pyle he will take care of you.