A lot of Historians might well agree with you. But I disagree on this point.
Modern history is a science. Or at least, it is more a science than an art. Historians may have hypotheses, but they must search for sources, categoring [sic] them according to primary and secondary, etc, in order to provide "evidence" for their theories. History is backed up by archaeological evidence, and archaeologists are most definitely scientific in their methods. For falsifiability fetishists, any historical theory can be disproved with the right evidence. While that may be hard to find, everything in history is in principle falsifiable.
The heart of the argument about scientific history is: is a historian specifically unbiased in his/her interpretation of the primary evidence? Is the historian unknowingly biased by the culture in which they live? I would answer this in the affirmative and thus history is not a science. This is a fundamental tenant of Historiography. I am also puzzled by what you mean by "modern history". Do you mean history within the last fifty years or do you mean historical methods since von Ranke?
As technology has improved, it has found its way more and more into historical studies. Things like X-ray scans, etc, used to find erased documents in old parchments. Things like putting the index of soldiers in the hundred years war in a database.
Merely putting data in a database is not History. It may come from historical sources but until someone places an interpretation on the data, it is just data. Even applying mathematics to the data is an interpretation of some kind.
History is a science, or at least, it is scientific in its methods. It's a worthwhile inclusion into an education.
If and only if you ignore the fact that the interpreters of primary evidence have unknown and unstated biases to their interpretations.
The subjects I was speaking of; things like art studies, poetry, philosophy, music, civics, etc, may all be worthwhile subjects, but they don't constitute an education. They constitute a pastime.
I would like to see a history of the Roman Empire without resort to their poetry, philosophy, or art for argumentation or explication. What it seems you misunderstand are the drivers of history are often those very things you dismiss as "pastime". For instance, Christianity has been a massive driver of history so attempting to write about late antique and medieval history without understanding the philosophical and theological arguments of the time (however flawed by the act of interpretation of a historian) would be unedifying.
One last comment. The primary sources are not unbiased themselves. Even archaeological evidence is biased in some manner (ie a burial is often times a statement made by the living about the dead and themselves with some meaning even if we have no idea what the meaning might possibly be). Primary evidence, especially documentary evidence, is often third hand: eye witness sees an event (first hand), eye witness writes down an account of the event (second hand and its own interpretation of history as it is describing something in past time), historian writes about the event (third hand and an interpretation on an interpretation). Even if the historian has more than one account that does not mean the historian has any better understanding of that event than the people who were there. The historian is not a third impartial eye on an event (or set of events). The historian must imagine the event and thus is already at a major philosophical problem that must be addressed before one can continue (I would refer the reader to a recent volume of the journal of History and Theory on the "presence of history").
As long as humans are the actors (with all of their irrationality, culture, and "pastimes") and future humans are the interpreters (with all the same plus the differences in language (something I deliberately missed out because translation of historical sources from one language into another is another huge source of subjective interpretations) and culture), History cannot be a science.
I just could not let this go. I have a question. How do you have a child "learn the history of their own country" without Historians? The last time I checked History was considered an Arts and Humanities subject. People who are by your own statement: "Arts and Humanities [are] students who know how to appreciate everything and know how to do absolutely nothing. People who can master the art of appearing intelligent whilst remaining shockingly ignorant. People whose ideas and tastes and practices are simply imitations of something that was actually original." You will have your hypothetical child taught by these people or is History somehow exempt in your scheme?
Numeric stability is probably not all that important when you're guessing.