* for the ones that are really good
Love is Sweet* - no long misunderstandings, second lead isn't too annoying but he does take a long time to let go, but he couldn't break the main couple's relationship no matter what he did, there's amazing chemistry (lots of intimates scenes) and a good amount of comedy and flirting between the leads. this drama fits your criterias the most
Accidently in Love
Go Ahead* - the leads take a while to finally date but their interactions are great
Go Go Squid* - very cute, lots of chemistry
Love Me If You Dare * - highly recommend this one, lots of chemistry
Lucky's First Love
Mars* - a bit old but very good, amazing chemistry
Oh My Venus
Qing Qing Zi Jin - this drama meets a lot of your criterias but theres an annoying male character who likes the female lead but nothing he does breaks up the couple cause their love is that strong together
Skate Into Love * - lots of chemistry, the second lead can get annoying a bit but his character is not supposed to be annoying, he can be unintentionally annoying but theres a legit reason for it.
Refresh Man
Sound Of The Desert
The Brightest Star In The Sky
To Love * - lots of amazing chemistry, main couple strongly trusts each other so there are no nonsensically annoying misunderstandings. the most amazing things about this drama is the chemistry, story and the strong trust between the leads that you rarely see in other dramas especially since this drama really tests the trust between characters