RAID 5 eh? Go to www.oraperf.com, register, and download the white paper on I/O tuning.

Best practice is to isolate big tables into their own tablespaces - smaller tables/indexes can be divided into categories by size and assigned to TS's appropriately. Small, Medium and Large Segment Tablespaces can hold both tables and indexes at once -- no need to seperate them.

You data files could easily afford to grow up to 4Gb.

Migrate to LMT for all TS's (except SYSTEM until you are at 9i), using uniform extents, as soon as possible.

I'm sure there are other things to add. anyone?