You’re comparing with an Ultimaker2+ and a Zortrax M200. Both of those are in my opinion at least one class “higher” than the Snapmaker2. (Note those are just 3d-printers and not a cnc and laser as well)
Another important thing: both of those are CoreXY printers (the head moves in X-Y and the bed moves down) So this also means that you’re parts, once on the bed will suffer a lot less “stress” while printing. The parts barely move at all and thus you can get away with significantly less adhesion to the print bed.
In that regard, I think you can still print the parts in the orientation you’re currently doing, but I would turn them 90 degrees so the orientation of the parts is parallel with the Y-axis movement. As your parts are top-heavy that should work a lot better.
Both of the other printers have a full enclosure that maintain the temperature a lot better than the Snapmaker enclosure
In the last pictures you’ve posted (I assume those are from one of the other printers?) you’re using a raft, I don’t see that same raft on the print on the Snapmaker. As it’s a raft connecting all parts together, that would help immensely as well.
Do I think you can build a full plate of your prints on the SM2? Yes, if you change the orientation, reduce the print speed and/or use a raft. Have a look at this post from @stefix Need help with the proximity sensor of the 3D Printhead
That’s by far the fullest print sheet I’ve ever seen on this forum.
Will it be faster than two separate batches on your current printers: I’m not so sure. If speed was your goal, then I’m not sure the Snapmaker2 was your best choice. (and it might have been better to just buy three or four smaller cheaper printers in stead and have them work in parallel)