Can anyone actually provide specific examples of Tendou being a jerk or truly uncaring to anyone? All that's ever made are broad statements about how horrible he is. Name moments in episodes and let's see if we can discuss whether or not he's actually being a jerk. That's the only way this conversation can go anywhere.
Last episode of the show. Kageyama is just sitting on the side of the road, slowly and obviously PAINFULLY being transformed into a monster by the stupid charm things around his neck. Tendou comes across him and knows that the what the amulets are doing to him, does absolutely NOTHING to help him, which would be as simple as taking them off or at least informing him what they're doing, and just walks away. Was Kageyama an asshole earlier in the series? Absolutely. But he did NOT deserve that kind of treatment. That really can't be seen as anything but a dick move.
Tsukasa doesn't bother me at all, because, unlike Tendou, there are actual consequences to his actions. He just swaggers into Kuuga's world, does his thing, acts like he's God's gift to mankind, and what happens? People die. A LOT of people, including Yashiro, who he obviously respected. Yes, the Grongi were already killing people without him, but his appearance accelerated the situation. When he's a dick to people, he's usually called out on it, and usually has to work to try and gain their trust. And he also blatantly shows that he has trouble empathizing with others, acknowledges this problem, and states that he has to rely on his friends (specifically Yuusuke) as his conscience. He's arrogant, yeah, but with this not-so-subtle undercurrent of self-loathing and insecurity about the fact that he's afraid all of the negative propaganda surrounding him might be right. I really don't get any sense of insecurity from Tendou, nor do I really see him be fallible, EXCEPT in God Speed Love. God Speed Love basically fixes Tendou (and a lot of Kabuto's issues in the process). We see him fail. We see him frustrated. We see his mask finally slip and we see him vulnerable and insecure. And in doing so, we see a Tendou that is infinitely more likeable. GSL Tendou is AWESOME, not because he's always right, but because he fucks up, and has to DEAL with that. I know why he's willing to sacrifice himself to create a better future, because he's already lost everything in this one.