"Interesting times" has a subtext. On the surface, it seems like a blessing for prosperity (eg. may you live a long life, may you have many children) because "interesting" may be taken in a positive way. However, as Tim points out, the meaning of "interesting times" would also include no peace, constant drama and possibly danger. In this case, "interesting" is used as a euphemism for "horrible / awful / dangerous".

"生不逢时“的反义？

Someone once told me that this is the translation of a common Chinese curse. I don't know if that is actually true. It seems that by using this phrase, you would be wishing something positive. But in fact, it is usually understood to be the opposite. You would be wishing someone to live in a time with lots of drama and with no tranquility.