Chinese is part of the "tonal" group of languages. That is, as you wrote, words are pronouced with different pitches (tones) and that changes their entire meaning. But its grammar and syntax are rather simple: no gender, no tense, no singular or plural form. For instance, in English you'd say something like: "My mother, she was wearing very nice shoes last night". In Mandarin, it will translate roughly as: "My mother wear very nice shoe last night".
Korean is an agglutinative language (like Japanese and North American native languages), with a very sophisticated syntax. It's really really tough to learn for someone whose mother tongue is Indo-European.
English is not that tough if your mother tongue is part of the Indo-European group of languages. What sets English apart is its lack of consistency. That being a "testimony" to all the influences it experienced. An example of its lack of consistency can be illustrated like this.
What do you call one of these little white pieces of bones that we have in our mouths? Tooth. Right there, this word is a bit awkward, in the sense that its plural form is expressed in the middle of the word: tooth - teeth. This is not unique to English, but it's very rare. Also, the inconsistency of English comes largely from the fact that it does not use the notion of roots to create new words. To keep using the word "tooth" as an example, how do you call the professional in charge of taking care of your teeth? A dentist. Tell me, what is the relationship between the word "tooth" and the word "dentist"? None. In French (my mother tongue), for instance, the word "tooth" is "dent" and you see a "dentiste". See, "dent" -> "dentiste". That's only one example, but there are many others.
On the other hand, English is a synthetic language, which makes it very convenient to create new words. For instance, the rather complicated French word "analgésique" becomes, in English, "pain killer". See, this pill kills the pain, therefore it's a "pain killer". This characteristic explains why English makes good rock'n roll songs and good stand-up comic lines. On the other hand, it's not very descriptive and could, in some occasion, create ambiguity, especially when translating to other languages. For example, the very well known slogan "Don't drink and drive" is acceptable in English, but it becomes unacceptable in French, which requires much more explanation. That's why French is so appreciated by novelists and poets: its "power of evocation" is remarkable.
Never let the facts get in the way of a good theory.