I have mainly two candidates for upgrade from the Aptus 75 I have now, 1) Hasselblad CFV-50 and 2) Leaf Aptus-II 10.
The advantages of the Hasselblad from my point of view is that 49x37 50 megapixels is a form factor that suits my work very well (and is my ground glass scoring), as it's a CFV back it can be expected to have more stable value due to the V system's value among collectors, and here in Sweden Hasselblad has good representation. I also have good experience from other Hasselblad backs working in the cold. The disadvantages is that the display/built-in demosaicer is not good enough for critical sharpness check, and that the Kodak sensor is not fully as good as the Dalsa in pure technical terms.
The advantages of the Leaf Aptus-II 10 is that I'm used to the interface, it has working 100% sharpness check and it has the Dalsa 6um technology, and its price/performance is likely one of the best out there, especially now when Aptus-II has been discontinued and thus lost some of its attraction among pro photographers. The disadvantages is that the 56x36mm format (3.1:2) is not to my liking so I'll nearly always need to crop in post-processing which takes away a little bit of the shooting satisfaction (having everything "right" directly out of camera is a special kind of satisfaction, and with a 56x36mm sensor that won't be happening as often).