Though I basically agree with other answers, I will suggest other approaches:

**Stop playing pathfinder**

Most of your problems (2 and 3) seems to come from the complexity of the rules, either because the DM don't know them well enough to keep the pace interesting or because players always have things to check. Pathfinder's rules are among the most complex ones I know. Simply choose a simpler system, or one your GM knows better.

**Rotate GMs**

A player who have never GMed before can lack some empathy toward the GM. With a bit of experience as a GM it is easier to tell when the GM is waiting for players to talk and when he has a speech to do and don't want to be interrupted. Of course it may not completely solve the problem, but it can't harm trying.