Choosing which point of view (POV) to use when writing a novel can be tricky. Sometimes the choice is abundantly clear; sometimes you are one third of the way into the novel before you realize your POV choice isn't working.
DYING TO REMEMBER is written in third person (he said, she said) because the structure of the novel requires it. I switch scenes within each chapter, jumping from one character to another, feeding the reader pieces of information to raise the suspense and their interest before switching to another scene and picking up another thread within the story. Unless your main character is present in every single scene, an impossibility in DTR since it jumps from one country to another, first person (I said) won't work.
I loved using third person for DTR because I got to inhabit the minds of three primary characters and numerous interesting secondary characters and that was fun. To effectively use third person, the writer must switch gears with each character and spend a little time inside the new character's life. It is essential that each character have their own nuances, their own way of speaking, of moving, their own flaws and strengths. Nothing bores me more than picking up a book and having every character mysteriously sound just like everyone else. Each character has a unique way of thinking, of speaking, of being and when using third person, it is the writer's job to breathe life into each character, no matter how minor that character may be.
The benefit of using third person is the freedom to wander through your setting, seeing details and scenes through various viewpoints, developing your characters from inside their heads as well as from outward behavior, and the ability to rapidly switch gears, intensifying the pacing of your novel.
SHADOWING FATE is written in first person. I chose this because Alexa has a strong, unique voice and is herself the crux of the story. Using first person gives the writer the ability to infuse the entire story with one character's voice, viewpoint, and inner conflict, all of which are essential to the FATE series.
Using first person can be tricky because the writer no longer has the freedom to wander through other characters' minds and instead, must convey a wealth of information about other characters' motives, personality, quirks, strengths, etc. through what they say and do around the main character. Careful use of dialogue and action become essential as is the necessity to allow the reader to discover each character and plot detail at the same pace as the main character. There is a subtlety and complexity involved in feeding information to the reader through the main character while keeping the main character ignorant of its true value or meaning.
For me, choosing the right POV for my novel involves considering the pacing, deciding whether the plot can advance through scenes involving only my main character, and understanding if the voice of my main character is strong enough to need center stage.