Okay, first off, Natalie Portman's acting in AotC was like Shakespeare compared to her deadpan monotone throughout most of TPM.
Secondly... about Jar Jar... yes, he was clumsy, annoying, impulsive, stupid, and prone to trouble. THAT'S WHY HE WAS BANISHED FROM OTOH GUNGA. His own PEOPLE didn't even like him. But what happened to him by the end of the film? He had done some pretty important things, enough that Padme felt she could trust him as an aide and the representative in the Republic. Nobody would have ever given Jar Jar that chance if they'd all given up on him because of his faults, as his own people did.
Of course, the intelligence of Padme's decision pretty much single-handedly caused the Clone Wars, but there's something to be said for having faith in someone long after everyone else has given up on them.
Anakin and Padme... well, there was really never any opportunity for Padme to display any sort of growing affection for Anakin. She may have felt some attraction initially, but the way Anakin kept eyeing her predatorially probably turned her off, enough that her attraction wouldn't show. Still, they did have the opportunity to get close while they were on Naboo, so we did get to see that she liked him. Being a Senator, though, she could guard her feelings outwardly a lot easier than most. Especially not an emotionally volatile Jedi. When they were about to die, she figured "hey, I have nothing to lose, may as well tell him."
I don't see Jar Jar's proposition of emergency powers as being convenient to the plot; it was perfectly natural given the situation. The Military Creation Act was under debate. The Senate has already proven to act too slowly to be of any real use in emergencies (re: the Naboo Blockade in TPM), so one of Palpatine's aides suggested to give the chancellor the capability to "cut through the crap" and take immediate action to save the Republic. By making it seem like something Amidala would do (even though it prolly wouldn't be, seeing as she's opposed to dictatorships), the goal of getting Jar Jar to THINK she would played him right into Palpatine's hands. Trying to be an opportunist and prove to Amidala he was capable, Jar Jar took the initiative without the forethought (which he doesn't have) to think of the longterm ramifications of his actions.
I love Star Wars.😀