Package that does multiple installs.

You can create a single policy with multiple pkg payloads. I have found in the past that these will install in alphanumeric order, so name your pkg files accordingly. Add a reboot to the policy.

You can create a post install script to run the secondary installs. Add it to the main pkg, and add the others as cached. once the main pkg has run, it will then launch the post install script and that will do the rest. Add a reboot to the policy.

Some other method, there are some alternate ways of completing your task. I would probably use a compressed file, that has the pkg payloads included, it then has a post install script that will expand the compressed file, and then one by one install the pkg files. This then goes into a policy with a reboot added to the end. For me I find this method to be the most reliable and flexible, plus I am using it a lot so I am used to it. Its a bit like the second method, but is totally controlled by the script, which will not run until the compressed file is located on the Mac and so you know all of the files are available.

For the workaround I ended up using a custom trigger at the end of my successful policy to re-install the existing policies for browsers. I omitted the reboot.