Satin Doilee, thank you so much for the inspiring, so very thorough and thought-provoking critique~! :'D
I colored my first post additions edited in about his appearance with purple. And the following are my answers to your queries~
Would the name Rajinder be alright?
Indeed he could notice and take into some account that there may be benefit not just in his own part after confirming the possibility of his own when making decisions. More often than not he would give help especially in dangerous circumstances. His self-interest has some gambling quality to it. At the very least, the risk-taker in him will be seeking out the challenge to strengthen and improve himself through further testing his survival, competence, and mentality in adversity. And he can come across as lacking in lamentation when affirming the exercises of his own discretion while discussing dire outcomes.
His motivation toward his own satisfactions stems from and is fueled by his desire to continually endeavor to be self-sufficient. But also this mentality is like earth over feelings looking for more harmonious relations with his family that he has unknowingly kept buried beneath and is indirectly addressing through his striving toward fending for himself first.
With of course his three traits linking together also on the battlefield, Rajinder recognizes higher ranks are defined by more experiences, skills, authority, knowledge, and wisdom. And so he can execute given commands, but he can also work to assess the battle circumstances and process the strategy's intended efficiency while aiming not to simply follow blindly.
"Why is there such high tension in his family?"
Rajinder has often been lectured with comparisons between himself and less than admirable traits of his birth parents, including but not limited to lack of seriousness and being lackadaisical when he is having trouble grasping teachings for instance. It bothers him whenever he hears all this, when feelings of continually falling short of his elders' expectations are inflamed, and he regularly reminds himself of such times so as not to forget that interaction comes with trials and difficulties.
"Does Fujita see his other family members as parental figures, or just people who provide a place to sleep?"
His elders are seen by him as his parental figures.
"Who is the most parent-like person to him?"
To him, equally each of the trio that is his grandmother, uncle, and aunt are considered by him to be more parent-like than his birth parents.
"Despite their differences, these family members raised him... does he feel like he's indebted to them at all for caring for him?"
Yes, but he as an odd take at expressing his gratitude that reflects his personality. He is of the mind that unceasingly working towards providing for his own contentment first is a step above being miserable and inadvertently shoving his gloom around figuratively speaking.
"How does he feel about the parents that left him?"
As a child he felt entirely betrayed. Though now for the most part he recognizes his parents absence as one of many factors in his life and ill feelings about this return to him less frequently.