Have different "Options..." for two different time machine backups?

If anybody could help me, I'd be very very grateful. Please bare with me...

I use a partitioned external hard drive with my MacBook with two partitions for (A) Time Machine and (B) files essential for my work but are too big to have on my MacBook hard drive (e.g. a ton of 5 GB photoshop files).

I'm scared to death of dropping my external hard drive and losing all of the files on partition (B).

I just bought a new hard drive to use as a "master backup". I'd really like to use Time Machine with it, and have it back up two things:

• MacBook hard drive (just like Time Machine is typically used for)
• Partition (B) on my external hard drive (the one with all of the files essential to my work, but too large to be on my Mac hard drive)

Is this possible? I can see that external hard drives are excluded from Time Machine by default, but can be "un-excluded" under the Time Machine "Options..." page in System Prefs. However, I don't want partition (A) on my original external hard drive to back up partition (B) on the same hard drive, but I do want my new hard drive to back it up.

Many many many thanks in advance!