I've played through the game multiple times in all three paths.
While you do pretty much visit the same areas in all three paths, you do completely different things in each, which, in my opinion, warrant three separate playthroughs. Just save right at the decision time and you can easily do all three.
I personally don't think any path is significantly easier than any others, but I do think that Wits is definitely the hardest. If I had to rank them, I'd say Wits is the hardest, followed by Team, followed by Fists.
All three paths converge before you get to Atlantis and end exactly the same.