I'd highly suggest looking at RPG systems specifically designed before World of Warcraft.
Regardless of how you feel about WoW, there's no denying that the impact it had created ripple effects that stretched far and wide throughout RPG's and gaming.
MMO's tried to emulate its design in a desperate effort to stay competitive (which arguably had the opposite effect) and even singleplayer games occasionally adopted a few inspired ideas. Pretty sure even D&D 4E's changes were inspired by certain WoW-related trends.
So if you want a wider palette of ideas, you might be better off looking back just a few years. Here's a few examples I could name that have mechanics that might diverge from what you're normally familiar with:
Star Wars Galaxies
(Pre-NGE, before they tried overhauling the gameplay to emulate WoW)
Spiderweb Software
(Specifically their slightly older games, at least in my opinion.)
Mortal Online 2
(Heavily inspired by SWG, with a dash of Bethesda "do thing to improve skill in thing" approach, and a rather unique skillbook related system)
And also look into some tabletop/pen and paper RPG's that aren't based on D&D or D20. A few that I've come across (though have minimal experience with):
Burning Wheel
The Riddle of Steel
Mythras
Aye. I was sadly late to the SWG game, only getting a taste of it within the emulation community, but even then I got an excellent impression on just how solidly they designed a lot of things. The camping system, housing, econ, crafting, etc. I'm not kidding when I point at how much inspiration Mortal Online 2 draws from it. Unfortunately, it has some brutally hardcore open world pvp, and not in a remotely forgiving kind of way. (A little too rage inducing for the amount of time I have to spare these days.)
Fucking Smedley, lol. Arguably he bears a fair bit of responsibility for Planetside 2 being such a faint echo of the first game. And then things went even further downhill for SOE.
I'd highly suggest looking at RPG systems specifically designed before World of Warcraft.
Regardless of how you feel about WoW, there's no denying that the impact it had created ripple effects that stretched far and wide throughout RPG's and gaming. MMO's tried to emulate its design in a desperate effort to stay competitive (which arguably had the opposite effect) and even singleplayer games occasionally adopted a few inspired ideas. Pretty sure even D&D 4E's changes were inspired by certain WoW-related trends.
So if you want a wider palette of ideas, you might be better off looking back just a few years. Here's a few examples I could name that have mechanics that might diverge from what you're normally familiar with:
Star Wars Galaxies (Pre-NGE, before they tried overhauling the gameplay to emulate WoW)
Spiderweb Software (Specifically their slightly older games, at least in my opinion.)
Mortal Online 2 (Heavily inspired by SWG, with a dash of Bethesda "do thing to improve skill in thing" approach, and a rather unique skillbook related system)
And also look into some tabletop/pen and paper RPG's that aren't based on D&D or D20. A few that I've come across (though have minimal experience with): Burning Wheel The Riddle of Steel Mythras
Aye. I was sadly late to the SWG game, only getting a taste of it within the emulation community, but even then I got an excellent impression on just how solidly they designed a lot of things. The camping system, housing, econ, crafting, etc. I'm not kidding when I point at how much inspiration Mortal Online 2 draws from it. Unfortunately, it has some brutally hardcore open world pvp, and not in a remotely forgiving kind of way. (A little too rage inducing for the amount of time I have to spare these days.)
Fucking Smedley, lol. Arguably he bears a fair bit of responsibility for Planetside 2 being such a faint echo of the first game. And then things went even further downhill for SOE.