Good question here, I would say... 以后 （In the future) 自从 (an event) 以后... （Ever since an event...) 后来 （After completing that) This is usually to be used at the beginning of a sentence。

when using 后来, you talk about result/what happen afterwards and it is usually in a shorter period of time. For things that have happened already. For example, 他们家的小孩很努力的读书，后来(eventually) 考上了一所名校！(Their child study really hard and eventually enter a top school)

以后 = "from now onwards". 后来 = afterwards due to a reason. 父母双亡, 以后是孤儿了. Both parents are dead and from now onwards [we are] orphans. 父母双亡, 后来家寒无亲. Both parents are dead and so afterwards, the family /is empty/becomes poor/ and no relatives.

just to add to the previous answers, 以后 can also refer to a certain or uncertain period later for example： 30年以后：thirty years later 5个月以后：five months later 一段时间以后, which means after an uncertain period