After you learn one new language, the next one is always easier, no matter what language it is. Even though you have to learn new vocabulary and rules, you already have learned what kinds of things you will have to learn, and it maes it easier. Many people consider Romance languages sucha s French and Spanish easy,.because their structure and rules are reasonably consistent. When I began studying German it was surprising how similar it was to English, you van tell they come from the same roots. So if you know English you will find german quite familiar in some of the word roots. But you should not feel like you need to pick only the easiest language. You can study any language you want with success. I would ask rather what language interests you, what countries interest you, and what subjects. For instance, if you want to read about science, quite a bit is written in german. But if you wanted to read ancient history, greek or latin would offer many books to read. So follow your love, and your interest!

The easiest language to learn is the one you have a passion for. This include the culture, people, history, or any other reasons. It is all in the mind. If you like it, it will be easy.

why don't you learn any of the 56 different languages that are spoken in RP China. maybe you discover something you didn't ever suspect that was so interesting.

if you already know chinese and english, maybe japanese is easy for you. i mean you won't have much trouble with kanji, some words come from chinese and there are also some words that come from english, also there's lots of resources online, some for learning and some for entretainment like anime, maga and dramas. give it a try.

why don't you learn spanish??? it isn't too easy, BUT when you finish this latin lenguage you can easy start with some lenguages like italian or portuguese, those lenguages are too similar. Three lenguages by one's prize, it's a good idea.