I've moved my business machines up to Windows 8.1 recently myself. It can be quite nice - I actually like it as well, though I personally have no love nor need for the Metro / Modern toy side and just don't use it.
So yes, I have to admit, with some additional 3rd party stuff like BigMuscle's Aero Glass tool, it's pretty good.
You did make one statement that caught my eye: "It really felt like a less animated, but more speedy Windows 7"
During the (very thorough) evaluation we did here to determine if we could move up to Windows 8.1 (from 7; we skipped 8), I set out to determine whether Windows 8 really is faster.
After extensive testing on the same hardware, it turns out it's NOT faster, really, except for one key thing: Booting up. Primarily that's the only thing, and part of it is because Microsoft has integrated what used to be called hibernation into the shutdown/bootup process. In head to head comparisons, with identical setups booting from SSD - and eliminating the hybrid shutdown/bootup (which we found had downsides we weren't willing to accept), we found the difference in bootup speed was just a few seconds, with Windows 8.1 being ever so slightly faster.
But beyond that, one of the most important things an operating system does - provide access to files - is actually slower in Windows 8! You read that right - Windows 8 is slower to access files, and 8.1 even a bit slower than 8.
If you have both Windows 7 and 8 on equivalent systems, and especially if running from SSD, try this:
1. Open Windows Explorer / File Explorer and navigate to the root of drive C:.
2. In the files (right) pane, select all folders and files, right-click, and choose properties.
3. Time how many seconds it takes for the Properties dialog to stop enumerating the files.
A healthy Windows 7 system will be able to count up about 20,000 files per second on an SSD. Believe it or not, a Windows 8.1 system will deliver only about half that performance! Benchmarks that show actual read/write performance show a reduction in throughput on Windows 8 as well, as compared to Windows 7. I could hardly believe it and I did the tests many times over.
Other things, such as operation of controls in the Windows interface (e.g., as measured by the 2D benchmark in PassMark PerformanceTest) are also a little slower on Windows 8, believe it or not. We did quite an extensive evaluation.
So why do people feel it's faster?
I believe most folks compare a loaded-up Windows 7 system with their freshly installed Windows 8 system, and would sense the very same "speedup" if they were to install Windows 7 afresh. That, plus the fact that MIcrosoft's hybrid bootup really is a good bit quicker than a full shutdown and restart in Windows 7, makes it "seem" faster.
Bottom line is this: Don't think that Windows 8 is going to radically speed up your computing experience. It really doesn't, and in some cases can actually slow the same operations down a little by comparison.