A few things;
First of all, Leaf Box is a homeopathic device, it can't actually do most of anything it purports to do. It's not on EV-CAN, where all the information is it's supposed to modify to make B mode/gliding/etc. possible.
So we will definitely never implement the Leaf Box. We do implement a lot of the features LB supposedly adds though, including B mode and gliding.
We also implement bidirectional CHAdeMO, but this requires a separate module (as it needs to intercept the QC CAN). Also it's still quite experimental, as with a lot of features.
Anything we do with the MITM module that causes issues can be resolved with Leaf Spy or, in a really bad case of our hardware failing, bypassing the MITM board and returning the car to its original state (and then clearing all errors). You can't really 'brick' the car this way, although there are instances where you absolutely do need LSP. We're trying to resolve this issue by making a hardware alternative to leaf spy pro, but progress on this is very slow.