. . . some of the tech is a little wonky, here at the end.
For instance, both parts of "In a Mirror, Darkly" were quite fun and pretty well-written, and it was nothing but joy to see the TOS Constitution Class ship rendered in full HDTV-quality CGI glory. (That said, I wouldn't have minded a little revisionism insofar as adding a faint blue glow to the warp engines and deflector, but that's just me.)
However, the ship was much weaker than she ought to have been. I mean, sure, the Defiant completely owned everything around, but only her phasers seemed to demonstrate the sort of authority one would've expected. The torpedoes were rapid-fire, but not as devastating as one might've expected. (Perhaps they simply hadn't figured out how to set them for max yield?)
Then we come to the final two-parter starting with "Demons". A neo-Nazi-esque Dr. Evil (or the Romulan copy thereof, though that's entirely my guess) takes over a comet-redirecting superlaser on Mars. He threatens aliens with it, and uses the FTL verteron destructo-beam to strike the moon northeast of Mare Humorum (at, what I might add, are terrible angles . . . Earth shouldn't show up in that shot at all, and Mars should've been roughly in the direction of the badly-placed Earth). His takeover occurs via a lunar facility with warp drive capable of propelling it at speeds of 25-100c (depending on whether one uses the screen time or the stated five-second warp jump).
(To the show's possible credit, there are indications in the episode that the facility-ship might've normally been capable of take-off and relocation on the lunar surface already, with the warp drive just a nice addition. But it's still a reach.)
The shot at Mare Humorum by the comet-redirecting verteron beam produces an enormous blast on the lunar surface, which leads one to wonder just what the hell kind of megacomets that verteron array was playing with previously. Judging by the crater Tycho also visible in the shot, the dust cloud covered hundreds of kilometers of the surface, and assuming the original crater to have been only one-quarter the size of Tycho it was 21km across!
And if the thing was meant to redirect comets, why is it an FTL beam? That's my main problem with the idea. Having this as an FTL beam just makes it too uber-fied. As Paxton says, he can fire on ships with it. So where was such a beam in the Bajor system when Cardassian ships would fly in uninvited? Why were the Cardassians so pleased over their planetary defense platforms . . . basically mini-space-stations with ship-like weapons . . . in "Tears of the Prophets"? Why no beams coming from Earth in ST:FC or BoBW? The Borg cubes should've been pummelled all the way in. And, of course, we find that the verteron array of six uber-beams is a relatively small facility, apparently unmanned. What, no miniaturization so that it can be put on starbases or even ships later? And what's the range limitation of this uberbeam? Assuming it can go 100c, what was to ever stop Cardassia from zapping the shit out of Bajor or DS9 within a matter of months?
In short, what should've been the case is that the beam should've been STL or lightspeed-only, of atomic-level yield, and used to threaten fixed locations like Earth cities, Starfleet Command, et cetera. Earth apparently doesn't have planetary shields at this point, so it would be believable. An STL or lightspeed beam of significant-but-non-uber power would've been more than enough to defend the array if ships came knocking in Mars orbit, with tracking systems aboard the mining facility enabling the array to hit the ships. But having the array able to smack ships around system-wide is just too much, and just about kills the idea of ships altogether.
End of rant.