OK, here goes. A reasonable conjecture is one that suggests further research to find confirming or contracicting evidence. Any conjecture that does not have within it the suggestion of possible disconfirming evidence is not part of science.
Theories are, in general, conjectures that are rich in detail and which have withstood many years of inquiry.
Regarding astrology, to the extent that it attempts to make predictions, the predictions are wrong. For the most part, what passes for astrology in newspaper colums is just randomly sorted platitudes that apply equally to everyone.
First you say the predictions of astrology are generally "wrong," then you say they are platitudes that could just as easily apply to anybody.
I do not consider astrology to be a strong science. It fails, by and large, to connect direct observation and testability with predictability. But I consider it to be science inasmuch as it is a body of "knowledge" collected over time.
Evolutionism, to the extent it attempts to reconstruct history, is not much different. The assumptions of evolutionism make for an easy way to construct platitutdes that could just as easily apply to any thing. It is apparent that evolutionism may be confusing common ancestry for common design.
It it no mystery that, if one takes the fundamental assumptions of evolutionism seriously, he will be able to interpret the evidence accordingly. The same goes for creationism. I don't think either one belongs in the science classroom per se, but I think both views are worthy of consideration and discussion.
I happen to be a young earth creationist. Although I do not have an exact figure and can only surmise from texts and evidence that have come my way, millions and billions of years are not necessary to explain what we see today. My understanding is based on what has been recorded in human language and reported through the generations that have preceded me. So far the manner and degree of order demonstrated by the universe leads me to agree with the biblical texts which declare it to be the subject and object of an almighty Creator.
If others want to come along and say this it not so, then I'll leave it for them to explain how order can come about apart from an intelligent agent. So far, as you know, I have hardly been convinced.
But again, this whole discussion, while it has a place, is outside of what science in the strict sense is all about.