I tried the first Trails in the Sky several years ago and didn't really like it.
Played for something like 10-15 hours and even though the combat was pretty fun the story just wasn't very interesting. I've seen people say it gets better later on, but I've never liked this sort of "it gets good after 20 hours!!!" sort of thing. It felt like it missed more of a hook, and the main character (the girl) was annoying.
Trails stories always comes in 2 games, 1st is the setup where you learn about the world, characters and political situation, the 2nd game is where shit goes down, TiTS FC is the setup SC is the payoff, Zero no Kiseki is the setup for the payoff in Ao no Kiseki, Cold Steel 1 and 3 are both setting up the payoff in both CS 2 and 4, TiTS the 3rd and Hajimari both set up the next arc/s.
Even then I'd say Tits is the slowest in the sub series since it had to establish so much about the world and the events that later games will follow.
You need to be in the mood for TiTS FC to really enjoy it and stick with it since SC is Sooooo good.