I'm currently two sessions into my second campaign with the same GM. To give a background to the real question, it's worth pointing out a few reasons the first campaign fell apart.
1. It used Monte Cook's Arcana Evolved, which is a seriously flawed rulebook
2. We were constantly expected to chase after the plot, but information was scarce. The main villains never tracked us down, and NPCs had no clues to give. Worse, the GM did not design this as a sandbox game, so it basically became a game of "find the rails."
3. Everywhere we went, we were surrounded by NPCs who were more powerful than us. The GM had a penchant for large pitched battles where our party were barely-contributing spectators.
4. The GM, for whatever reason, kept throwing high CR encounters at us because he wanted to make us run away.
Our solution to (3) and (4) was to recruit NPCs into our party. This led to a feedback loop where combat was balanced for the party + NPCs, so we kept recruiting more just to stay competitive. So our actual PCs were solidified as ancillary to the campaign. It didn't help that most of the table was disinterested in actual role-playing, so the characters had zero investment in the story. It also didn't help that many of our characters were a bunch of Bilbos; the characters tried to make the most rational decision (based on real world logic) and had little to no interest in adventuring for its own sake.
In the end, the campaign finally imploded due to player rebellion. We were one session away from the final battle. The villain revealed his master plan, stole the MacGuffin from us, and ran off toward the town we had been using as our home base. What ensued was a large argument within the party about whether or not to follow him. Because our characters were largely incompetent compared to everyone else in the world, one side thought the town could handle itself and that we should go find reinforcements somewhere. The argument lasted over an hour, the GM would have ended the campaign before he let us go off the rails, and the player arguing the hardest for finding reinforcements had his character leave the party permanently. Thus ended the campaign. I personally stayed out of the argument because my character was dead when it happened. The words, "Shut up, you're dead," did come up when I tried to voice my opinion.
We took almost two years to cool off, the most vocally angry players dropped out, and the GM just started a completely new and unconnected Pathfinder campaign. I was hesitant to join because of all the problems with the first campaign, but I wanted to give him another chance.
So here's where the new problems start. The new campaign is in a homebrew setting. Basically, there are two superpowers locked in a Cold War, with any actual fighting going on between satellite nations. Both factions are highly authoritarian military societies.
All the PCs are level 1 nobodies from both factions who have been drafted into a joint investigation regarding a destroyed embassy. There's a little tension due to the baked-in party schism, but that hasn't been too much of a problem so far.
So now we're in this society where every NPC both out-levels and out-ranks us, which means the PCs aren't in a position to refuse any demand an NPC makes of us. We're basically just being pushed around by superior officers from plot point to plot point. In the most recent session, we've been put under the direct command of an NPC soldier. We followed the plot to a city, and our permission to even be in that city is contingent on this NPC taking control of our actions. So somehow, the GM came to the conclusion that the problem with the first campaign is that we had too much freedom and we needed an NPC babysitter.
I don't want to be in a campaign where my character is a slave. I much prefer a game where the GM is flexible, willing to improvise, and capable of working with the players to find adventures that hook them, both in and out of character.
I see three ways to cope.
1. Quit. The GM has shown that he's probably not going to stop railroading, so I could give up and try to find a new group. Probably the sanest option, but I'd prefer to find a way to make this work because I don't have any other leads on an RPG group.
2. Kill the NPC. The vindictive side of me really, really wants to do this. Out-of-character, I see him as a shining example of what my GM is doing wrong. In-character, he's an enemy soldier who stole my investigation and made me his slave. I tried ditching him once, to no avail. He was badly injured when we first found him, but I passed up the chance to coup de gras him in his sleep. Killing him now would take coordination with the rest of the party, which is probably another campaign-ender.
3. Have my character turn into a rebel freedom fighter. Currently, he's a zealot in the service of one of the two major players. It could make sense for my character to be so disgusted at how this joint investigation deal worked out that he loses faith in his own side.
Is there a fourth option I'm missing? Does anyone have advice on how to find the fun in an authoritarian setting with an authoritarian GM?