I imagine both of those softwares may have some licensing that may prevent redistribution, (Im assuming you’re referring to the ookla speed test cli package and not the on in the current deb/ubuntu repos that doesn’t really work). However you can build your own images and include those packages in the packages directory and they will then be included in your images. I currently build mine with ooklas speedtest package.
Other than that VyOS supports containers so you can install adguardhome and speedtest cli through that so there is no need for that to be included natively in the iso:
Or create your own container using alpine linux and install speed-test cli yourself within that (since there are no official docker image for that as it seems) and then install that as a custom container in your VyOS.