You may base this on potential if you'd like
I'm going to give my opinion and if my question isn't clear after that, please let me know
My vote goes to Dragon Age 2
The "tank" in that game quite a few options
To start, your main choice of equipment
2-handed vs Sword and shield -
2-handed felt like a beserker gone mad with its large attack radius and its high damage output
Sword and shield felt like a tank should with its "charge" into combat as a normal attack, smaller attack radius and high damage absorption (you'd have to play it just to realize how great of a job they did making this character fun)
they had side options between taking more damage, short to midrange stun abilities, helping out the party or just doing more dps ^^
then you had a choice between your secondary classes between a templar, reaver and beserker
Templars focus had you with taking down magical enemies with their silence abilities and buffed resists
Revear would take a pounding only to increase damage with -life... could have made it very interesting to find that line of safety and damage efficiency
Beserker sacrifices defense for increased offence.. this was the least cool of the 3 (just wasn't done well, although had potential)
This was but 1 class in DA2, all 3 of them were done as well as this guy
i love it when games think less is more (you don't need 50 different classes to have diversity)