I've decided to take a rest from TCT and start working with Polgar's Book. I'm right now at the "mate in two" part of the book, currently at problem 400.
The "mate in one" were all so easy that I could do most of them without thinking, but some "mate in two" are quiete challenging, specially the ones where the enemy kings lies in the middle of the board.
I don't know how it relates to the tactics I was training earlier, like forks, skewers, double attacks etc, but that's certainly helping me, and I could almost say they are helping more than the ones I was doing earlier. Working with this mate problems is very different cause I know what to look for, and thus I can consider less candidate moves, and work deeper on the variants. I think that's really improving my calculating abilities.