Been there and done that, I always ended up with spare space in the program partition but out of space in the data partition. The problem gets worse the more partitions you add.
Multiple smaller partitions made sense on the amiga where a reboot would cause the filesystem to validate, but I'm not sure what problem you're trying to fix with multiple partitions per drive on windows.
With multiple drives I'd still probably try to raid0 or span them.
Not necessarily a "problem trying to fix", as it is a documents management and organization solution. Need to back up your data? Just click "backup D:" or where ever, no mucking about picking specific data directories on C:. Same thing with data recovery, if all your documents are stored in one partition it makes it easier to recover, also applies to defragging, etcetera.
Or maybe it just appeals more to my OCD.
Also Windows lets you resize partitions on the fly, oftentimes without even needing a reboot. It's not as bad an OS as some people here make it out to be, LOL.
RAID0 is great, I have two Plextor SATAIII SSD drives running in RAID0 on one of my machines and it's smokin' fast, but I wouldn't recommend it for critical data storage.
