Hi Zorphius, I think you got the subject of the topic just correct. What have I gotten into... :-). I am currently completing a SCCM 2007 to 2012 migration and had a lot of questions when I started. I saw you having some similar questions and had to reply, because I know the mountain you are looking up to. In the last 2 months I have had major headaches fixing some of the issues relating to SCCM 2012 and especially databases and installation and I can tell you that there is a lot not in the books or even on technet. Anyways, I try to anwser your questions as good as I can:
1. I definately would not use the migration tools. What could really come in handy is the collection migration. I have used that and saved a lot of time. I was also looking at migrating the packages, but I all the paths will change so you have to edit them all anyway. I choose to recreate them in the new environment and in the mean time clean op any unneeded packages that we had. A consultant that I spoke on the SCCM 2012 course also told me that he had a lot of issues with the migration tools and had done 1 migration with them and got so many issues that he did the rest of his migrations manually without them. Advice that I took for granted.
2. No, you can do the AD forest discovery and set up your boundaries. You could even discovery your devices. Just make sure that the automatic client installation is not enabled!!! ADministration -> Sites -> Client installation settings in the ribbon -> enable auto site wide lcient push installation. That would really mess up your environment. Just install them manually. The sccm 2012 client seemed to uninstall the old sccm 2007 client automatically, so that is handy with migration. Although I did not yet test that thoroughly. Also, do not forget to not enable pxe on your distribution points.
3. Gotcha moments. Oh yeah! SQL server with several instances and reporting services... A lot of issues here with ports, security rights, default instance etc.... If you run into any, maybe I can help. I for example made the stupid mistake to try to install the reporting role on the primary site server that did not have the database site server role installed. De DB was of course on the SQL server but SCCM setup just lets you totally complete the setup of the reporting role on a server that does not have the DB site server role installed instead of giving an error message that it must be installed on a server with the DB site server role.... Also some people suggested that reporting services database could only be installed on the default instance. They were wrong :-)
4. Not specifically other than browsing the internet and combine all the information there is to find. That was really the hardest part. I found the information on this site very practical sometimes. http://www.windows-n...manager-guides/
5. No not really. Currenly completing the test environment and I will then setup a migration plan after that. I have written an installation manual of 60 pages or so, but that is company property and am not allowed to share that.
6. Hmm... I know what you are trying to say, but we do not give our helpdesk a lot of rights other then remote control and adding a computer into an AD security group to deploy a package. Maybe some query viewing. What I am going to do is create a helpdesk handbook for sccm 2012 with pictures that describes the most basic tasks. I did not yet find anything on the internet.
Hope this helps a bit. You currently already busy on the project?