I'd suggest just demo'ing the bike. I understand that everyone has their specific use case and desires for battery capacity and motor (brand, power output etc). I learned a few hard lessons with my relay in not considering this fully when buying into the fazua system.
The Bullit is a special bike, at least in my opinion. I've ridden the vala extensively, I've ridden other long travel bosch emtb's (wild, regulator, shuttle lt, crestline) and the Bullit stands out as a ride experience that was un-expected. I expected it to be a burlier vala, and it's not quite that... it's one of those bikes that is more then the sum of it's parts or it's design decisions. There is a frame stiffness component that I have experienced, particularly on the wild and the shuttle lt, that make those bikes feel much better at the limit then they do just riding casually. This bike has a goldilocks situation going on and I am starting to wonder if the sizing of the downtube for the 750-800wh batteries is adding orders of magnitude more frame stiffness.
This bike has a ride dynamic to it that is most closely related to crestline... but for me, it's a far more intuitive bike to jump onto and ride. I was more at home with regards to cornering and how the bike changed direction then I have been on other long travel ebikes. It does feel like a relative of the vala when cornering, but it is not at all related to the vala in terms of suspension performance. I have a gen 6 nomad and while I love that bike, it is not a hover bike and does not feel like a downhill bike. The bullit literally erases parts of the trail. The last time I felt a bike perform like the bullit did last night in laguna, was shuttling with my v10 dh bike.
Suffice to say, I realize that the 600wh battery is polarizing... but you really need to ride this bike before putting it into a box and assuming you know what's up. It just so happens that the 600wh battery and re option are perfect for my usage of an ebike... but honestly even if it weren't, this bike is so special that I would just suck it up and deal with it. As I said, this bike is more then the sum of it's parts... without riding one, I fear that you really don't have the full picture. And I can't believe I'm saying this, but no, you cannot ride a vala and assume you know what this bike will be like. After riding this bike, I can say that anything that would have compromised the ride feel and suspension performance would have been a non-starter, at least for me.
Simply put, the suspension performance of this frame is only something I've experienced a few times in my 25 year riding career. This bike is scary capable, scary fast and is a complete nutter. It makes the vala look downright civilized.
Edit: One last thing about the suspension performance. I am not a huge fan of the float X... I generally find it a bit harsh. In the past, I have struggled to find the right balance of rebound damping, spring support and compression settings that give me the feel I want. I still find that true while riding the Vala... it does better on that bike then almost any other bike I've ever ridden it on, but it's still leaving me wanting more. I cannot say the same for the Bullit. I have more setup to do and of course I'm in the honey moon phase... but I didn't leave my first ride on this bike wanting more from the rear shock. I am still a bit miffed at the (lack of) value proposition of a 9,500 usd bike that doesn't have top of the line suspension, but I do not feel the need to upgrade this shock immediately. I have never said that about a bike with a float X before.