Yeah I've poked at the WISP Toolbox. Looks promising but about what I've already written, hehe. I too would gladly pay a yearly support contract for what you suggest.
What I mean with "Google Translate" interface is that the language was very strange. Like instead of just using the existing English DD-WRT interface, someone took another version and ran it through Google Translate instead. The 150 has a bunch of very ominous buttons on the WAN page about port bindings and groups that really don't make any sense. I spent a couple hours playing with it and I was able to get it to bridge customer traffic out the WAN port and use DHCP for the VoIP side, but I wasn't able to separate the VoIP part from customer data with it in Router mode :(
Would you be willing to share some screenshots of this thing out-of-band? I contacted our sales rep about possibly getting a set - with similar notes about how the 150 is kind of a bust - but haven't heard anything.