Microsoft Skype for Business Server 2015
By "pure reverse-proxy", which scenario are you using for"Are you deploying this BIG-IP system for Skype web services (reverse proxy)?" The lyncdiscover hostname is present for me in the RC6 template that's on when I choose to either forward RP traffic to Lync/Skype servers or forward it to another BIG-IP.
For Office Web Apps, we can update the guides with manual steps for colocating on the application virtual server, similar to what's in the SharePoint guide today. However, we believe that most organizations will use a dedicated WAC environment to be shared between SharePoint, Lync/Skype, and Exchange, that uses a unique IP. Also, creating separate configurations for WAC in each iApp is problematic, since the configurations in each template will drift.
I'll create an RFE for the multiple SIP domain work, but we don't have an ETA on it at the moment.