Is ARM EABI v7a System Image and Mips System Image important? I noticed that what makes installing SDK packages so slow is because these two packages take too long to be downloaded and sometimes it hangs on these two. Do you really need to download these two packages on every API version in the SDK Manager.
These system images just enable you to run Android emulator with processor of some architecture (depending on system image version; for example, Android 4.0 supports x86) and Android SDK doesn't require these images at all. If you use your phone (or some real device) for android development and don't use emulator at all than you don't need to install them at all.