Yes, it's silly to have more than 2 1x1 interest checks. Even if you have a "niche interest" There's really nothing to be gained by splitting up your interests over a series of topics, especially since most of these interest checks are nothing more than a list of ships or a story you'd like to do.
Example of typical list:
Burger king X Wendy
Slime bunny girl X Brad Pitt
Gender-bend Voldermort X Kratos
Example of typical plot pitch:
My gym teacher/cafeteria chef sees your vampire hunter (read:chuunibyou) tearing their way through tokyo. Because my parents have recently passed down a pair of golden chopsticks, my family's cherished family heirloom, it's my job to keep Akihabara safe from annoying otaku like you. But there's an otaku convention coming up, and now your otaku isn't so annoying anymore. In fact, my chef finds you kinda cute...
And there's actually a pretty good reason to keep the RP end of things pretty light in your interest checks. Because chances are you're going to end up reworking a lot of that to suit your partners tastes. Like maybe someone wants to chase Brad Pitt as a slime koala girl, or maybe they'd prefer to be Mc Donald instead of the King. Maybe the example in the plot pitch only really works if the other player gets to be the gym chef, or maybe they'd rather the story take place in America.
People who make interest checks may have a craving* or idea in mind, but people who search them are more interested in picking a player they are going to click with. Things like your age, interests, desired writing level, posting speed, personality, those are the things people are more interested in. And while it may help to have a plot or pairing that grabs people's attention, those are the details that are going to make someone actually message you.
Not that I look at 1x1 interest checks. I'm more likely to hit up a friend if I have the desire to do something like that.
*Craving is the most cringetastic word in roleplaying ever, and I suggest everyone stops using it ASAP.