Rick, my main issue with partitioning a setup, since I'm using a RAID array, has more to do with making sure the primary partition is properly sized. I've seen too many issues crop up where the C drive/partition was thought to be of sufficient size, only to run short on space later. Plus, if I go and break the RAID, I'll end up needing to rebuild everything. Not what I do for fun.
I've not needed to reinstall the OS on this system since I installed Windows 7 (64 bit)... I might do it in the future, but that will be onto higher performance drives, also in a RAID array. Those drives will most likely be smaller...
I've not gone through an image capture/deploy with Windows 7 just yet. I have a set of tools that I prefer to use, so I just need to get familiar with the latest versions. But, chances are, I won't use that for this system anytime soon.
I still need to carve out the LUN from my SAN to make a network share to use. Right now, the SAN is being used to hold the VM's for my ESXi host. Chances are, once I can get another host server, or two, I'll reuse my current host as my main system. Or, I'll just keep using what I have for hardware... Dual quad core E5345 Xeon's power my working system... Plus 16GB of RAM, and 3 750GB hard drives (RAID 0)... Displays (two 24") are fed by a GeFroce 8800GTX video card... Even at ~4 years old, the system still has plenty of power in it, and life left. Of course, my ESXi host is sporting a pair of E5405 Xeon's and 16GB of RAM...
I do try to 'cleanup' the system every year or so... More to get rid of files that I don't really need on it than anything else.
I've seen plenty of issues crop up when using multiple partitions on systems, pushing the user data off to a secondary partition. Far too often, if the OS gets hosed, you'll need to rebuild the user data, or go through a lot of work to try and bring the old data in for the rebuilt OS to use. I usually just say F it and pull over what I need from the old account into the new one and rebuild the rest. Since I have the SAN now, I might push my profile off to that. Maybe... Of course, now that I have my domain name set on the LAN (I have an actual Windows Server 2008 R2 AD DC online) it should make things a bit easier. I was playing around with different settings on that for a while... Wanted to make the structure more logical. Plus, I have three external domain's that I can tap. I basically have a mini-data center here in my living room.
Anyway, before I install anything that could be invasive on this system, I just have to make sure it's not going to whack my VMware apps, or my other LAN tools, and such... I do like how Kaspersky keeps me safe... It did it again tonight when I was checking what my hosted email flagged as spam... Kaspersky blocked some potential nasties, and told me so... I need to renew that one pretty soon...