POW Hmm, not really for Oregairu, it's very iconic. The only decent one I can recommend might be
"Irregular at Magic High", though it's not as character-oriented, and more plot-oriented. Another might be "Oreshura", but it's kinda cliched and boring.
For "Hige wo soru", it's not really a novel, but a manga (and anime adaptation). "After the Rain" is a romance story that's of a similar vein.
For bunny girl senpai, well, that one has some interesting counterparts, though once again, not quite the same. "Steins;gate", "Erased", and "Kokoro Connect" (the character "Balloon Vine" inspired me to write a couple of ideas down for a new novel, but my pen hasn't touched any paper yet). Highly recommend the former and latter, though Erased has a rough ending (not emotional, just ends bad, leaves a bad taste in your mouth).
That's about it, fresh out of ideas beyond that.