I think Snow Leopard is great too, it's too bad they dumped it in favor of Lion and what's followed.
Lion was one of those "full of good intentions" ideas. In my personal opinion (and I think in the minds of many others), it was an attempt to make the desktop OS behave as much as possible like an iPhone or iPad.
Not everybody of course, but users pretty much hated it. Saving changes to my files before I say so, or even bothering to ask if I want the changes saved? Launching all the apps I had open when I shut down my computer last time on the next startup? Who says I want them open?
You must have a newer machine than what I have, because Mavericks runs horribly on my late 2009 Mac Pro.
Only slightly. A 2010 Mac Pro that came with 10.6.4. I do have 16 GB of RAM in it though since I run a lot of memory intensive apps, such as Photoshop, Illustrator, the Premiere Pro suite.
Over the years, I've seen a lot of complaints about every OS that has come out, and the common issues of "it made my Mac worse/slow down, etc." Other than truly reproducible and verifiable bugs, I've honestly never had any of these problems. And I attribute that to never, EVER installing an old OS over a new one. I always install a new OS to an erased drive, then reinstall of the apps I use. I do this over a period of about a week as I continue to get work done in the previous OS.
Once I have the new OS and everything I use setup, and test it for incompatibilities or other such things (usually always the need of a few apps that have to be upgraded to work correctly in the new release), then I switch over. I keep using the new OS for a couple of weeks before I decide for sure it's working as expected. I then archive the previous OS and everything on it to a .dmg file and erase that partition. If something does come up that can't be worked around without waiting for a fix from Apple or a third party software vendor, I can always restore the .dmg.