I'll offer one additional thought on cabs to possibly be a bit more helpful than my last post. Since the purpose of SanAmp products is to produce a sound highly reminiscent of "fill in the blank" amp/cab combinations (which can vary depending on the particular SansAmp and its settings), going for a more FRFR type cab might offer the best result. In theory between Crown "pure power amp for gain only" and a "no additional coloring cab" the SansAmp amp/cab output would be exactly what you would hear at the volume you set on the amp.
Some of the largest outdoor shows I've played were through SansAmp products where the FOH and monitors were handled by the sound techs at the mixing desk. Everyone was pleased with the result and I was using the SansAmp product very much as intended by the designers. My suggestion to look at FRFR cabs would sort of put your set up in this same operational model and offer you a chance to get every voicing out of the SansAmp without competing or added coloration. .
You sometimes hear people complain about a SansAmp when run into the input of a bass amp and cab. In these cases you have an already voiced amp and cab either being fed a different "simulated amp/cab voicing" which doesn't blend well or a doubling of the effect which can be "too much of a good thing". In some cases it works out fine, but it's always a bit of a gamble when using a product differently than what it was designed for.
Try out some cabs if you can and test out the thoughts I just offered. I think that's the only way to be sure you'll get the results you're looking/listening for. I hope that's helpful.