Certainly you can do it. Not mention in your country, but also in Chinese speaking countries and regions there are many people who can not write or read, particularly in China. In English world, no offending, it is called ¨illiteracy¨ and I believe such people exist too but they speak fluent, at least, more fluent than someone like me or even English teachers here. As you said it saves you hundreds hours if you just want to practical. If I were in your position I might make the same choice too. if you want a reason to make you more comfortable to make such decision I might offer you one. Chinese is not like English that many science / tech / business research are used as a written language. Without learning Hanzi may lost some fun and art or culture, but it does save you a lot time to spend on oral instead. (Being a native speaker, learning writing Hanzi takes incredible long time from childhood as well.) And the last I know many western people who does not read or write at all but speak fluent Mandarin Chinese. It does not bother them at all because they do not have the necessity to read material in Chinese. What they need is just effective communication without misunderstanding with local people.

I think learning Chinese can't avoid Hanzi, because it's just like the character in English, it contents the culture and spirit of China, but you absolutely can start it from Pinyin as a begginer, just like we were in childhood.

I suppose it all depends on what level you want to reach. If you are just traveling and want to learn a few set phrases you should be ok with no knowledge of the HanZi. I am not very experienced in learning Mandarin, but... in my opinion, I think you are going to run into trouble very quickly if you are not learning the written characters. There are just too many homonyms in Chinese (I am talking same sound AND same tone). Reading through long sentences in Pinyin with no characters to reference could become confusing very quickly. I am guessing in the end it would be faster to reach an intermediate level of spoken Chinese if you are also learning the characters at the same time. Obviously, just like with the spoken language, you don't need to grasp the written language in its entirety to use it. It will not take you 2,200 hours before you can write "hello." Also, the first few characters you learn seem very difficult, but they get easier the more of them you know. EDIT: OH also, if you want to cut corners. Typing is MUCH easier than writing by hand. Typing is closer to reading than writing. You might be able to get away with typing Chinese. I know some people who can hold a basic conversation on a social media app, but couldn't write the characters.