What my user folders looked like at first:
Notice how the OneDrive and Podcasts folders stick out due to the Windows 7/8-style folders icons.
So I found an alternative OneDrive icon in the image shell32.dll in C:\Windows, extracted it and used that one (Windows 10-style icon).
Then I created my own podcasts icon. I used the Windows 10-style folder paired with the Zune podcast icon to create my own custom icon. Here's the end result:
All of the folders match, now!!
If you're interested in getting your hands on these folder .ico files yourself, they're attached below!
1) Download the ico files to a permanent location
2) Start with C:\ then navigate to the parent folder of the folder you want to customize (like C:\Users\[USERFOLDER])
1. Right click the folder, select Properties
2. Select the Customize tab
3. Click "Change icon..."
4. Then click "Browse..." and find where you saved your .ico file, and select it
5. Click OK.
Download: OneDrive.ico Podcast.ico
(note the Podcasts shell folder only exists if you've installed the Zune software)