Chinese personal names are usually one or two syllables and family names are usually one syllable. That’s not too different from the average English name, really.
His birth name was Deng Xiansheng, for what it’s worth. Xiaoping was a nickname.
When the Japanese adopted the Chinese writing system, they used their native pronunciation as well as adopting the Chinese pronunciations when using the characters in compound words.
The native pronunciation is usually longer. 小林新太郎 Kobayashi Shintarou would be a typical male name, with the first two characters, Kobayashi the family name and the final characters the given name.
For family names, there are one, two and three character names, and usually one or two characters for the given name.
Nitpick: Dictionaries define surname as family name, regardless of its position.
The definition of forename may be less clear. Dictionaries often define it as “gven name” or “personal name”, but I suppose the dictionary writer might have just ignored the case of Chinese…
It’s important to note that names vary considerably across India, with names it the south being longer in general. Also, these days, a lot of first names are sanskrit or religious based and are less regionalized.
As noted above, Tamilians didn’t really have last names until it was mandated, and they just picked what was handy, such as town name or caste. I’ve found that in Andhra, usage of last names isn’t important. You can leave them blank on forms, or just put the first letter. When referring to someone formally, you would say Mr/Ms/Mrs First-name.
I’m not sure how this plays into length of names, but Telugu has very few single syllable words. There’s a couple dozen prepositions or interjections, but virtually no nouns, verbs, or adjectives with one syllable. As names often originate from existing words or ideas, this may play a big part in lengthy names.