Ubuntu Installation :: Non-Mission-Critical Clean-Install Partioning?

I have been happily using Ubuntu for a good while now. It started out sometime around the end of '09 when I purpose-built a machine to continue using WinXP Pro as my primary OS, but using a ROMTEC Trios to mechanically switch to another hard disk, booting Ubuntu Karmic. I liked the fact that the Trios kept my two disks from "seeing each other", because, at the time (and perhaps, still now), I was not ready to keep the peace between a Linux boot and a Windows boot. It was simple: use XP for "day-to-day" for a while, then power down, flip a switch, and boot up Ubuntu to get my toes wet in the Linux world.

I very quickly developed an affinity for the Ubuntu experience, and ditched my XP installation in favor of a blank slate for Linux experimentation. The disk which previously contained XP has since housed various musings of mine, including Ubuntu Studio, Puppy Studio (yes, I am a recording musician), and straight Puppy, along with some recent tinkerings with straight Ubuntu Maverick (which I've had problems with due to what I believe is lack of driver support for nvidia-96).

BTW, my current primary install is that of the original Karmic install, but upgraded to Lucid...running just fine to this date, but wondering a bit at how I'm only showing 11GB of free space on a 160GB disk...I can't quite figure where the space has gone...the math doesn't seem to work in my head, but then again, I'm still a n00b in a lot of ways.

At any rate, I've gotten a lot of mileage out of Ubuntu so far, and I'd like to experiment with "pimping" a clean Lucid installation from the ground up (as I said, I'm having graphics driver issues with Maverick, and I'd kinda like to stay with an LTS release for the time being anyway).

I'm thinking that a customized partition scheme would be a good thing to think about, and the geek in me is inclined to reach beyond the installer defaults and even beyond the common recommendations of adding a separate /home partition. I've read an awful lot about the subject, and there are as many opinions as there are underarms, but I've just gotta ask it anyway:

For a single-user desktop, is there any efficacy in using separate partitions for /boot, /tmp, /usr, /var, /opt, and/or /usr/local? I know most that I can do without a separate /srv partition, but for the others, I just wonder if I can use separate partitions for both security and optimization reasons.