I see, a wider vat itself so that spills will be further away from the cutout, and a wider cutout so that spills fall into the machine away from the projector, that makes sense.
It should be possible to easily build a prototype of such a vat with some laser cut acrylic, another item on my long list of to-do experiments.
It seems that a wider vat might also be stiffer, but it’s hard to say whether it would reduce flex to the degree that it would impact print quality.