Hi
vvv000:
Thanks for reaching out to all of us. Addressing a few of your concerns:
"I learnt that my citizenship will bring the recruiters to compare me with all the Chinese students (who are quite competitive, especially the ones from mainland), being Chinese also means that I belong to an overrepresented pool of candidates"
--> Yes, this is a factor but there's nothing you can do about it. You can't change your nationality/ethnicity, so why fixate on this point? You have to focus on the elements of your background and personality that you truly believe help differentiate you. That's not an easy task but it can be done with the right amount of introspection and craft.
"...and to make everything even worse I have a very mediocre GPA. I do have valid reasons for it (depression and family business ) but I feel like trying to explain it only makes everything sound like excuses."
--> I wouldn't write that off yet. If you have legitimate reasons such as these, they can be addressed in the optional essay. Again, it's all about striking the right tone and putting a forward-looking spin on it. At the end of the day, all you can do is offer your best reasoning. Instead, focus on improving your GMAT score. That is the single best way to counterbalance an average GPA. Getting into the 700 range will be important for someone with your profile.
That all being said, LBS and HEC are top programs and I fear they will be tough for you. You should still apply if you manage to get the right GMAT, but I would also expand your list if you are really set on getting a master's degree. There are many great programs out there and you will find the right one!