The worst example of something that they did wrong, IMO, was losing Obi-Wan during the shots of Anakin fighting Dooku. One shot, Anakin jumps forward to save Obi-Wan (ironic, given his similar save of the Emperor from Luke in RotJ), but in the next shot Obi-Wan is nowhere to be seen.
Maybe he just rolled out of the way. ; )
As to the "we're out of rockets" (and the rockets in clear view)...
Chalk it up as a film flub.
Though, IIRC, in the novel they say "we're out of ordinance" but the movie is higher canon than the novel, so oh well. ; p
Getting Jango out of there would either require Obi-Wan to call for backup, or take Jango's ship instead of his (which would make a perfect setup for an escape attempt). The "old folks" DO tell him to arrest Jango and bring him in, so I guess they didn't think of that... oops.
One other thing I don't understand, is that in all the lower than movie canon they call Obi-Wan's ship a "Jedi StarFIGHTER" but where are his ships weapons? And why didn't he ever use them? Was he that outmatched??
I've heard one suggestion offered up to explain the "generations" vs. "years" problem between ANH and AOTC (other than something lame like "the republic was reformed after the sith war" or "Obi-Wan was lying/senile again")...
That Obi-Wan was speaking from a typically Jedi-centric position, and he was referring to the "generations" of students in the Jedi 'academy' as it were (I know there isn't really an academy per se, but go with me here).
So you have like in college, students entering as freshmen, and the same year you have other students who are just graduating. So each year, is a "generation" of students that are entering and leaving. So from that point of view, you just need some Jedi before that are training up (the first Jedi) and then 1000 years of graduations during the Old Republic. And of course all during that time.. Obi-Wan is saying... the Jedi Knights were guardians of peace and justice IN the Republic, a Republic, as Palpatine said, had stood for 1000 years.
And yes, we know there was a full scale war at the formation of the Republic...