jggimi's recommended procedure for partition planning for any new environment that has
unknown capacity requirements.
Step 1: Set aside all preconceived notions of disk space requirements for any individual partition. Ignore anything anyone tells you is "typical" sizing requirements.
Step 2: Install everything in a single, great big root partition. Don't worry, this is temporary.
Step 3: Use the application set / environment for some length of time: days, weeks, months, as needed.
Step 4: By using
du(1), determine what your hierarchy is actually consuming.
Step 5: Reinstall with your final configuration, or back up - reconfigure - restore.