Be warned, this gets wordy.
When voting, I initially had an idea of which seasons I preferred. And while I enjoyed 3 and 12 a lot, and while 1 and 5 will have special places in my heart, I ultimately voted for TAR 2.
Visually, it was just incredible. In spite of the fact that it was filmed in near-winter (?), the entire course had a summery feel to it that I really liked, due to the number of legs in the Southern Hemisphere. Despite that decision, there was a variety of locales, from the rainforest of Brazil to the sand dunes of Namibia to the skyscrapers of Hong Kong to rural New Zealand to frigid Alaska and the gorgeous view over San Francisco bay that finished the season. Could there have been more countries visited? Perhaps. But I think that each leg was effective as a part of the race course as a whole (ie I couldn't picture the season without the leg in Otago, or the leg in South Africa, or the leg in Northern Thailand, etc). As a plus, there were several 'notable' monuments visited - Christ the Redeemer, Nelson Mandela's jail cell, Sydney's Opera House.
The teams were good in that they represented a wide variety of types of people from different stages in their lives, which impacted their interactions with each other, other teams, and their approach to the tasks. I think a direct result of this is that you were able to see relationships evolve: some were obvious (Tara/Wil's gradual acceptance of their separation, Deidre/Hillary bonding), but others were more subtle (Cyndi taking a more active role in their relationship, Blake respecting Paige as a racer). While some had complex relationships, others changed internally (Chris/Alex being humbled, Peach becoming more self-sufficient); the combination of these led to a lot of the more meaningful moments in the season.
The tasks were great. They achieved a mix of being relevant to the culture, being difficult, and being entertaining from a viewer's perspective (in particular the Detour in Bangkok, the Roadblock in Otago). Even the tasks that were slanted heavily towards one of these still had their charms (the Nevis Valley bungee, for instance, or the final roadblock in Alaska). This of course doesn't include all the non-Detour/RB tasks: the hunt for the flower in Bangkok, the drive from Queenstown to Auckland, flying from Brazil to South Africa, which tested teams capacity to remain calm and focused in a stressful situation.
There were hilarious moments - nearly everything in the leg from Hong Kong to Sydney, nearly everything the Chas did, and even beyond that, most of the teams had something worth laughing about, even if it was unintentional in nature. There were heartwarming moments - Shola and Doyin in Mandela's cell, the teams cheering on the Grannies, Wil on the bungee (for me, anyway). There were moments that were just insane to watch - Mary and Peach being told 'They will kill you' if they went to their next destination', Tara vs. Wil in Hawaii, Blake in Bangkok, etc.
And then, of course, there was the finish. A slowly building relationship/rivalry between two teams, with their share of good times and bad, leading up to a leg and a half wherein Tara and Wil's relationship crumbles, and Chris/Alex seemingly become stronger than ever, ultimately leading to T/W at each other's throats, functioning solely to arrive first at the finish line while Chris/Alex, galvanized from their last-place finish in Hawaii and last-place status out of Alaska, attempt to play catch up. (I have to give it to the editors for not simply editing Blake/Paige out of the picture a la Jill/Thomas in LA). Regardless of your thoughts on C/A, there's no denying that the final minutes of the race are some of the most memorable in the series' history, from the effective scoring to the great camera work (at multiple times the camera will slide from Tara back to C/A).
Ultimately, I feel that even though the teams may not have been the most likable, the combination of teams, countries, tasks and circumstances of the season combined together to form what I think is the best season of TAR.
