Allstar and Echolink would be absolutely HUGE !!!!
I was thinking about a Clearnode which does Allstar, Echolink + DMR and Fusion and not D-Star for some strange reason but it's a bit big and no battery and runs off SD card and it's not ideal for car use because the OS3 os is on the firmware itself and you don't have to shut it down which would be a pain in the ass, if a future Openspot could do all this including D-star it would be absolutely amazing.
The OS3 is what allows me to use my Anytone 878 on D-Star, Fusion and DMR all from the one radio and not having to use my phone to switch channels or modes, I do all this from the radio thanks to the special features of the OS3 this makes it the best hotspot available in my opinion and Allstar would be amazing because it would hopefully encourage People away from these old and highly compressed digi modes which can be really difficult to endure.
The only thing that bugs me with allstar is that I would need a smart phone to change channels don't have to do that with the OS3 on digi modes so if a future Openspot had allstar it would be good if it can change channels from the radio using the special commands that can be programmed into the DMR radio like I do now for the digi modes.