Re: endless crashes
At least by running
you can actually see which ones take a lot of time so you can target those as to researching what they do. Another thing would be to install the systemd-gtk package and run systemadm which is a tool in that package. It will list the services and show a short description of what each does (it's not much, like "nfs-server.service" has description "NFS Server"). But I suspect in the near future they'll get the idea to put more information in there, or even put the systemd-analyze blame results into a tab so you can see it from there.