Yep, I agree on the part that the team with the best racing skills should win, not because they're female. But for this season, we can't deny that Nat and Kat and Brook and Claire are competent teams that deserve the win.
The one thing Nat and Kat have that many racers don't is their ability to stay calm during stress levels. Look at their performance in Ghana. Despite nearly being eliminated, they did not let that get to their heads and start freaking out and yelling at each other. Instead, they did what they had to, stayed positive, and finished the leg. We all know that panic does no good for the racers, neither does rushing through. Nat and Kat are always meticulous and cool, that's why they don't make mistakes. Also, Nat overcoming her fear of heights and Kat eating the meat at the FF despite being a vegetarian for 22 years speaks volume of their determination to win. They're smart to boot. During the previous Detour where almost every team was struggling, they did it systematically, showing that sometimes you might not have special talents (in this case musical), but you can use your brains. Of course, they're encouraging towards one another as well (have we ever seen them get frustrated with each other?).
As for Brook and Claire, from the very first episode where Claire got hit by the watermelon during the Roadblock and was in pain yet she persevered and their team still did so well in the end... I've been truly impressed by this team. They're competitive, fast, and never give up. (Recall Claire doing the bridge Detour in Norway in leg 5). Yes, they did make mistakes in mis-reading the clue which should not be condoned. But the fact that they realised their mistake, rectified it, caught up to the teams and still finish in second place, that was a feat in itself and I give them loads of credit for that.
Of course, I'm not saying that Jill and Thomas aren't deserving. I believe that they're a very strong and competitive team as well. Look at how fast they are, always coming from the back and still finishing well. But in terms of team dynamics, I don't think they have it. Thomas is always the one making decisions. He feels that he's the brains behind the team (from his constant mention about him having gone to a good college). This is a team race, not an individual race. And... They just bicker too much! Had they kept their attitudes in the first leg, I'd have loved them and wouldn't mind them winning as well.
Indeed, the team with great racing skills should win. And I believe that all three teams have them. But on racing skills being equal ground, things like personality and chemistry come into play. Nat and Kat might be boring but they're always nice to each other, and other teams. Brook and Claire might bicker a little sometimes, but they bring so much positive energy to the race. Jill and Thomas, if they're not bickering, they just fade away. So in comparison, I'd still want Nat and Kat or Brook and Claire to take it all.
As for wanting an all-female team to win, that is just a bonus, since we've never had that before. You know, if Connor and Jonathan had made it to the final three, I'd have rooted for them as well.
That's my take!