Mairimashita! Iruma-kun
robin my love <3 Ahem. Sorry. Got something stuck in my throat there. On a more serious note, the best way I can describe 'Mairimashita! Iruma-kun' is 'Poor MC gets caught up in something bigger than him, but he improves and achieves friendship in doing so.' The manga follows a similar structure to the classic action trope of growing in levels, but it also has a focus on the rest of the cast. While it is less so than Iruma himself (he is the title character, after all) I can say with certainty that this manga has made me fall in love with each and every misfit in Iruma's class, as well as every other character Iruma encounters. It's just a feel-good manga for people looking to feel good.
Kakegurui Futago
While I've read a few chapters of Kakegurui - Compulsive Gambler, I can say with certainty that Twin has given me a much more enjoyable reading experience. Twin follows Mary (or Meari, if you prefer) when she first starts attending Hyakkaou. Like Yumeko, she makes a strong entrance by beating the class bully. Unlike Yumeko, however, Mary feels like she's actually trying to strategize and win. In general, Mary was much more likable as a main character, and following her journey through Hyakkaou was beyond riveting. If you wanted Kakegurui but less horny, I believe Twin has got you covered. Also, Hoshizuka is for sure gay for Mary.
Shin'ai naru Boku e Satsui wo komete
Kanojo mo Kanojo
Though a smaller harem than most, I'd say Girlfriend, Girlfriend is for sure one of the funnier harem comedies I've read. While harem comedies usually rely on misunderstandings for their comedy, GFGF takes the complete opposite approach. All of the three main characters are absolute buffoons, and I adore all of them. The main character Naoya is probably one of the best harem protagonists I've seen. He shares quite a few traits with another fellow harem MC, namely one Rentarou from 100kanojo, and his combined idiocy yet earnest love for both of his girlfriends makes GFGF a much more enjoyable read than most other harem comedies. Also, Saki is definitely bisexual.
Kumo desu ga, nani ka?
Kumo-chan is a very good main character, at least in my opinion. Her ability to beat the odds and attempt to strategize during a fight makes her eventual escape into the overworld extremely satisfying to read. She has a personality, a lot of spunk and the ability to think quick on her feet, which makes every successful battle not only satisfying (due to her being born weak), but believable too. Not to mention the current chapters are popping the fuck off. If you have the time, please give Kumo a read.
Lazy Dungeon Master
I like the concept, but... it's really horny. Really horny. The MC is (thankfully) more of a feet guy, which I did laugh at, but you can feel the author's intent.
School Zone (Ningiyau)
While Yuri/GL is not necessarily my forte, I did enjoy School Zone Girls. It features a lot of romance options, all of which are good in their own way, and if you do love cute girls doing cute things who look generally shippable together, I believe School Zone Girls would be a good manga for you.
The 100 Girlfriends Who Really, Really, Really, Really, Really Love You