Light novels, especially those adapted into anime, are infamous for their tropes. Their stories often involve characters trapped in games or sent to fantasy worlds. The cast frequently includes a large number of female characters, many of whom are in love with the protagonist. The main character himself ranges from aggressively passive to do-it-all wish fulfillment. Little sisters who see their big brothers as more than just siblings are a dime a dozen. 
Given how frequently these elements are used, one common criticism is that light novel stories would be so much better if they would just not include them, but I wonder if that thinking is putting the cart before the horse. The way the light novel industry works, it might be better to approach it almost as genre fiction: the tropes are the starting point, and it’s what you do with them that counts.

Many series do not try to directly defy the tropes, but will twist and bend them. My Youth Romantic Comedy is Wrong, As I Expected (aka My Teen Romantic Comedy SNAFU) has a wimpy protagonist in a prominent love triangle, but he is forced to reevaluate his way of thinking thanks to the genuine friendship that forms between the three. Is It Wrong to Try to Pick Up Girls in a Dungeon? is actively modeled after a game-like world (with levels and experience and monster spawn points) and includes a hero practically every female character is in love with. Yet the personality of this main character, Bell Cranell, sets him up as someone whose childhood dream of having his own harem is offset by his gentle nature and kind heart. In a sense, these titles play by the rules first, as if part of the challenge is trying to work the same old materials into something new. The Monogatari series constantly changes up what we thought we knew about its female characters, rendering that harem into an ever-shifting enigma.

Not every work becomes a winner, of course. Some try in vain to differentiate themselves, only to be unrecognizable from the rest of the pack. Even so, within a given formula, there are subtle permutations that might not register with an outsider, but could be just the thing that causes the avid fan to choose title A over Title B. Perhaps this is part of why light novel titles get so excessively long at times. Not only is it a stylistic trend, but it might just be the most efficient way tell potential readers what this title has to offer. I Don’t Like You at All, Big Brother might not seem all that different from My Little Sister Can’t Be This Cute, but the former title implies a couple of things. First, it takes the younger sibling’s perspective into account more. Second, given that both titles are patently untrue, it hints at the little sister character as being more honest with herself.

Light novels (and works based on them) also should not be immune to outside criticism. Just because certain qualities and ideas are accepted by the fans doesn’t mean that nothing is ever structurally wrong. It’s the difference between evaluating a shooter-style video game from within the context of its own genre versus looking at the ways in which the genre as a whole depicts and glorifies violence. Both conversations can happen, and it’s possible to meet somewhere in the middle, as with Splatoon, which keeps shooter mechanics but de-emphasizes grit and death.

Light novels are not inherently the tropes described above, and many go well beyond the limitations associated with the format. But for those that choose to stay within those bounds, either due to personal desire, economic pragmatism, or market forces, those tropes might be better viewed as the cornerstones from which their stories are spun. Just as shooters necessarily must include guns, and vampire stories need vampires, genre light novels cannot simply be stripped of their well-worn tropes. They can be stretched and molded into new shapes, but getting rid of that core transforms them into something they aren’t and likely never try to be.