would that make daniil worse if his main colour was blue

don't know what you have in mind by "worse" but to me the red of his color palette serves his character in multiple ways: associated blood, of course, relating to his profession and the company he keeps and attracts, but also war, as he is belligerent in his vision and willing to go head to head with foes he has no chance of vanquishing, passion, danger, courage... it also serves to detach him from the muted/earthy colors of the characters around (and if you take the P2 models it directly contrasts him with Burakh, who has associations of blue [eyes and sweater] and green), and give him an almost like. "dangerous animal" color scheme (a number of [venomous] coral snakes have black and red and many poisonous amphibians like frogs have bright red as a color choice).

tldr i have no idea what you mean by "make him worse" but to me as someone who designs characters for fun (WISH i did it for profit) like. the red was. obviously chosen for a reason.