About the tones not being as useful ... I think there are cases, in which they matter. Take for example 熊猫 and 胸毛: "有 xiongmao 吗？" "Are there Pandas? " or "Do you have chest hair?". Another one: 时间 and 事件. Sometimes it gets comical, but natives can and some will be confused, when your tones are off by too much, and the conversation just started, so that the context is not as narrowed down. Context is key in the language. You can notice that, when you are trying to join a conversation between natives. Until you understand a phrase or most of a phrase, that gives you a hint for the topic they are talking about, you will usually have a hard time understanding anything.

I just tried the tool and it couldn't properly recognize a very clearly pronounced "吃" and instead heard some shi2. I think it needs more training data or something. Or one needs a good mic.