I built ply cabinets for my kitchen. Dado works fine and is helpful for assembly as long as the ply remains flat and there is just a bit of room in the dadoes for glue. If the joint is tight in dry fit, you will be in for a battle at glue up and there will be lengths to deal with that can't easily be clamped together.
if you can design things so that parts are glued if you're intending to glue - in a couple of phases on a really large cabinet, getting partial glue ups square and tight to aid subsequent, you'll appreciate it.
at the time I made my kitchen, I'd worked 20 years before in a factory where despite using cheap sides and backs, everything was rabbet and dado on the box with frames applied (different than you're mentioning) so I did what I was familiar with but dadoed the internal parts, too, which made glue up harder, but the boxes are incredibly rigid now and won't sag. that also allowed use of less hard ply (cherry face, poplar lumber core) and less thick (1/2 inch).
too, most of the feedback I got was "that's an antiquated and overly difficult way to make kitchen cabinets. Get engineered materials and screws made for them.
it definitely would've been easier.
Another option that was done in the US and may still be done custom in some cases is building a frame with lumber as a skeleton for layout and then building anything nonstandard to it. the kitchen that I removed was a combination of birch ply, but all of the nonstandard areas made to get everything to fit over wide spans was clearly partially built in situ and not in full boxes.
Not having a second knowledgeable person present for glue up, though, was the only real big thing I'd change - as impractical as it may be commercially to build cabinets with strong glued dadoes and rebate edges - it is amateur impractical only if things are too tight and glue gets a grip almost right away.
