Overall I really liked this season and the cast. The finale felt exciting, but I think we should give much credit to the editors here because if you scratch on the surface you find a slightly different story.
Firstly the show spent a sizable chunk of time on Lauren & Joannes lost clue in Toronto. What they did not show was that there was almost certainly an overnight rest here. That is the seaplanes took off in the morning the next day. So no matter how much time they spent looking they just ended up on the last plane and did not really loose any additional time.
On the main race day the team positions never changed. Anthony & James were on the first seaplane and they stayed in the lead the whole day. It looks like Sarah & Sam completed the task in the Santa's village just after them but we never see them in the same shot at the big man so I am pretty sure they actually were a bit behind.
At the irrigation task we only hear that the first two teams see each other, we never see them in the same shot so we can not see how far ahead Anthony & James actually are. Of course we see both teams get their next clue at the same time but this very much feels like editing. I did not get the feeling that Sarah & Sam really though they could catch up to Anthony & James in the final trip to the pit stop, which by the way was almost a hour away.
All that said I still think it was a good finale. While the tasks may not have given the racers much time to get ahead I think all of them gave racers plenty of chances to fall behind. That is you can not really complete them much faster than a certain time and the teams were close to that. There is of course potential to mess up but we did not really see that either.
So a big round of applause to the teams which managed to get here and did a good job in the finale