Recommendations Novels similar to Our Second Master? Romance with satisfying character development + karma payoff

Looking for BG romance similar to Our Second Master with plot points:

• Satisfying romance development
• Satisfying character development
• Hardworking/clever characters
  
• Weak to strong
• Loving more than looks
  
• No OP ability
• No love at the first sight
• Douchebag redemption

 

I can't think of any that fit all your criteria, ill just give some of my recommendations. (doesn't weak to strong usually include OP abilities?)

"The Healer Demands Payment!" not a lot of chapters to make an accurate judgment, but at least its a xianxia setting, the fl is a skilled doctor who came back in time but she isn't OP at least for now, and as all cultivation stories, she will probably grow. We only met one (possibly two) love interests but there are probably many to come. I am not confident the romance will be as you want it. At least the first love interest wasn't very well done imo.

"The Sword and The Dress" i mostly read the manga rather than the novel (this girl is a little wild) but judging from the manga, the romance should be cute, the fl is a bit OP and becomes weaker with little hope of becoming stronger than she used to be, so it doesn't hit many of your tags but i recommend it anyway.

"I’m Only a Stepmother, but my daughter is just so cute!" there aren't a lot of chapters so i don't know how it will go, and it probably isn't what you are looking for but it does hit quite a few of your tags as far as i can tell.

"I’ll Be The Warrior’s Mother" there are only two chapters so there's almost nothing to say about it but it looks interesting, i reccomend keeping an eye on it.

"The Tyrant’s Tranquilizer" this should have some douchbag redemption though thats only my prediction as there aren't many chapters.

Im sorry that i dont know any that fit your bill very well, i dont even know "Our Second Master" so i can't tell if i know anything similar

 

Rebirth of Han Yuxi
https://www.novelupdates.com/series/the-rebirth-of-han-yuxi/
It satisfies all your requirements but a bit skeptical about douche bag as the ML did stray once but was immediately taught a lesson by his wife and kids and he dared not do it again.
But if you thoroughly enjoy personal and character growth and romance, this is the way to go. It does have political intrigue involved and lots of drama too so if you're not averse to that, keep reading.

One of my absolute favourite novels of all times so forgive me for the long rant but you vould definitely ignore it as even if I tried to avoid spoilers, some fish might escape the net. This is from MC pova and is a rather long one.
After a sad and miserable death, HY is revorn as a kid again. Even if its her second life, HY has no OP abilities or emotional tolerance to hide/disguise all he remotions.
[From the very beginning, she has started to look for opportunities to strengthen herself. She is always seeking out and fighting for opportunities to develop any skill she deems important for survival in this cruel world. Step by step she learns chess (as it helps strengthen scheming skills ), medicine (cause you may need it anytime as a life saving means), history (when shearns that reading history can beoaden your horizen and make you moreopen minded etc.)
Even as a kid she startles her tutors and grandma with her tenacious efforts to learn as they realise that she's the kind of person who only needs a small gap to drill in and spread the roots which might be counter productive to their self interests as she might possibly overpower her halfsister who's being groomed as a future empress. Also because under the guidance of a kind momo she quickly masters the art of facial control and they're slowly being unable to judge her emotions.]

That's a brief summary of events from her initial phase of life but it doesnt end there as her struggle remain endless and she grows one step at a time. Slowly growing, commiting blunder, learning from mostakes, reading more books on political views, etc.
This is a very in depth book. I learnt a lot about interpersonal relations between family, couple, parents and children, subordinates,etc. Each stage of her life was filled with challenges whether it being as an unfavoured daughter, unsesirable wife, mother with 6 children with each having different personality and grooming needs, as a governess or an empress.
Another great detail is our ML. He is no OP person who excels at everything.He is a general and is unrivaled in warfare but politics/ governance is his weak point. He knows MC is good at it and provides her with a platform to do so. He was initially a very rigid person who was through brainwashed to loyalty to emperor regardless of his dissatisfaction with his way of governance. It took MC a lot of effort to convince him to rebel and better the life of his miserable comerades with his own hands.
ML is an ordinary man and makes a lot of mistakes too.
In short this is a journey of two very ordinary people as they proceed to live an extraordinary life uptil their death at oldage.
I just cannot stress enough how many minor issues have been dealth with intheir journey which can be insightful for everyone.