Ooooh, a rewatch! I've not joined in on one of those, could be fun!
Though honestly, I have grave doubts that watching the 5th-7th seasons in a short timespan will do anything to improve or clarify the storylines...I'd think it'd make the flaws and plotholes more evident, as Moffat doesn't seem to be much bothered by inconsistencies and/or may have counted on the spread-out broadcasting span to help keep contradictory bits from being remembered too clearly by the audience. Anyway, on to some thoughts of the episode:
There's very little establishing of character here, as once the Doctor timeskips over the 12 years it's pretty much all go-go-go, racing around and trying to stop the Earth from being broiled. The bit before the timeskip is wonderful though, and being that it's not only a post-regen episode, it's also a showrunner-reboot and a promoted move to BBCAmerica (bringing in a whole new audience), so it's understandable to put an action-y adventure as the format, drawing in new viewers as they reboot the look of the show (new Doctor, Companion, TARDIS, Sonic, etc). The Doctor's new characterization is "yes, I'm totally the Doctor, and totally all-new" yet "here's many ways in which I echo my predecessors", which is kind of all over the place, but Matt Smith's performance holds it together well enough. Young Amelia is brave and curious, but Amy has a more fiesty-and-petulant combination, which can be entertaining but is also kind of a heavily-treaded character type/trope (especially in sitcoms, which is one of Moffat's previous showrunning experiences and may be relevant to later developments
).
And speaking of later developments...the Atraxi secure Prisoner Zero because Amy dreamt it into its true form; and Prisoner Zero only used Amy's mind/dream because it was forced to find a different form than one of those that Rory had photo'd with his phone. Rory's pseudo-sleuthing and phone were crucial to the Doctor's plan to save the planet. Without Rory, the Doctor would've had no way to expose Prisoner Zero to the Atraxi (the Doctor might've been able to set all counters to 0 but wouldn't have had the pics of the alternate forms). So Rory's existence is vital to the Earth (and everyone on it, including the Doctor) not being burnt to cinders; if somehow that existence were removed or erased, the world should look radically different...
One other observation is that there's a definite start of a trend where the exact (or nearly so) amount of time for a deadline or timespan is cited. The Doctor's timeskips are mentioned of course, but the bit that I found weird was the Doctor calculating that he had no more than 20 minutes to save the world. I'm pretty sure that more than 20 minutes of runtime elapsed after that declaration, and that even leaves out the scene changes/edits where the Doctor is walking about town with Amy, or vehicles are being driven around to the hospital. I don't know why there was that emphasis on the timing when it was then pretty well ignored; a simple "we haven't got much time" would work, or just make the Doctor's calculation turn out an hour or some other length of time that could plausibly cover all the action that gets skipped in between the go-go-go pacing of what's on screen. It only bothered me a little bit here, but since there come along at least a few other instances of the Doctor citing specific timespans for reference, I figured I'd mention it at the outset.
All told, despite my picking at it, the Eleventh Hour was still a pretty fantastic way to kick off the everything-new-again 5th season. The interaction with the Doctor and Amelia with the fish fingers and custard was clearly a memorable highlight (at least in terms of character moments), while the rest was a flurry of activity, which made for an exhilarating first outing.