Father Skywalker said:
no, U R misenterperting this entire situation/thing
Star Wars Episode 3 the revenge of the Sith-darth sidious becomes emperor palpatine and gets rid of all democracy in the galactic republic.
Star wars episode 4 a new hope-the rebellion alliance exists to fight the bad guys.
in between- the empire does a lot of atrocities and stuff like that, that we are never shown in the films
Also in between-people don't agree with/don't like the empire for political reasons/they are dissenters.
the bad guys (the empire) uses the death star to destroy alderaan in order to show to the rest of the galaxy not to mess with them. Kinda like how Joseph Stalin is be-all-end all paranoia dictator/tyrant to the fullest extreme of paraoid schizophrneia, that sicko ordered purges to eleiminate all dissenters-even if the dissenters were just innocent ordinary everday unarmed civilians-It was not to spite Prinecss Leia or Jimmy Smits. even if there was no rebellion, aldearan would still have been destroyed. They already believed her, it was not for interrogation.....
the empire dissolves the senate for god-knows-why
You're reading these stories two-dimensionally. He does destroy Alderaan as a demonstration of power, yes, but he also does it despite her. Watch the scene, listen to the dialogue, look how they behave. These aren't the flat characters you find in the prequels, where all plot points are spoon fed to the audience. They resent each other, she's trying to be awkward and he's being malicious, whilst also fulfilling his overall agenda. He threatens her planet to get information and does what he was going to do anyway by blowing it up. He still uses it as an interrogation tool first, he uses what she says, and takes pleasure in blowing her planet up in front of her. He later orders scout ships to check Dantooine for a rebel base (off camera, its all in the dialogue) and is shocked that she lied under such duress, at which point he orders her termination.
He dissolves the senate because they have reached a point where they don't need them. That's made painfully obvious by the prequels; Palpatine has been manipulating and orchestrating his way to power all the way through them, Ep4 is where his rule is cemented and there is no more galactic senate because he doesn't want/need them. He is in a position where no politician can oppose him (the Imperial armies/navy follows his orders!), which is why its mentioned that "the last remnants of the old republic have been swept away." There is no way this could be any more obvious, other than having a narrator explain it all to you whilst you watch it.
So far all of your arguments are focusing on one motive for this, one motive for that, but you're failing to spot parts of the context/plot that are established, and failing to realise that characters can and do have more than one motivation at a time. That's what makes them interesting.
I think you need to watch these films again, and really try to think what the motivations for these characters are. Maybe then you'll understand what I'm saying. Until then I have nothing more to add to this debate.