1) That model has a custom UI, which means for me double the UI work just to deal with that specific model's UI
2) Based on a different firmware code base than what I use, and merging that new code base is near impossible at the moment, partly because of the many changes, and partly because no other router model is supported by that new code, so I would have to drop support for ALL other models to switch to that new code base
3) Code looks pretty much unfinished at this stage, with frequent releases from Asus, and numerous issues still left
4) That new code base has even more portions than before that are now closed source, including the OpenVPN code and the networkmap service.