Sleepy Hollow

So I watched the premiere episode of this new supernatural-horror TV series. It struck me as a good premise and reasonably good execution for the first half of a low-budget two-hour movie, but the way the plot was stretched and pushed to make it the starting point for a continuing series threatened to run it in the direction of the ground in very short order.

Two things in particular:

1) The way Ichabod's dead wife shows up in his dreams to deliver expository lumps. I have the sinking feeling this is going to be a regular feature.

2) At the end, Ichabod tells Abbie that there's some sort of Biblical prophecy declaring that they're going to fight Evil as partners for seven years, which just happens to be the typical length of run for a successful TV series.

There are some other things I didn't quite understand:

3) I liked the idea that the Headless Horseman is on a quest for his head, but if it's been successfully hidden for 250 years, why upon learning its hiding place do the heroes a) blab the secret to everyone in sight, b) rush to dig it up without any particular new and better hiding place in mind, with c) the Horseman out looking for them?

4) If the Horseman will be so invincible and doom-bringing if he gets his head back, then how was Ichabod able to decapitate him so easily in the first place, and why hadn't the doom arrived then first? (Note that Tolkien specifically addresses and answers the comparable question: If the reason it's so vital to keep the Ring from Sauron is because he'll be so powerful with it back, then how was it ever taken away from him in the first place?)

5) If Ichabod and the Horseman have both been in a stasis box for the last 250 years, why have they returned now (maybe that'll be learned later), and what's with the supernatural events occurring during the interim?

We are told that there are two covens, of the good witches and the bad witches. Ichabod's wife was one of the good witches. Well, that's sure fortunate, isn't it?

Ichabod's arrival in the 21st century is one of the most matter-of-fact forward-leap time-travel scenes I've seen. He seems very fast at assimilating, and Abbie is very quick at accepting him. But what can one expect of a former history professor at Merton College, Oxford (let's let that solecism slip), who was drafted (!) to fight against the colonists and who then changed sides, a course of action that didn't endear Benedict Arnold to many when he did it in the opposite direction. I was immediately thrown off by his use of the word "triage", which I thought anachronistic and indeed it is: though the word did exist in the 18C, it meant sorting for quality (as wool or coffee beans); its use in field medicine, as here, dates from 1930, according to the OED. Let's just skip over the part a moment later where he says that his wife was a military nurse.