The entire rathtar sequence was the exposition for what Han had been up to for the 30 years since Return of the Jedi. I understand why people think it's out of place, since it's not really related to the core plot, but I don't know that I can call it a complete waste. It tells us that Han's up to his old ways, smuggling stuff, hiring crew, losing crew, doing stupidly dangerous and reckless jobs, getting himself into trouble double crossing anyone and everyone. It also furthers the bond between Rey and Finn by having them work together, and propels a disinterested and disengaged Han into the main plot and the whole mess with the Resistance and Leia/Kylo, by forcing him to commandeer the Falcon and leave his freighter behind. Then it gets the First Order on their trail when the gangs spot BB-8 and pass that along. On top of all that it ticks off a Star Wars monster scene and some classic Han/Chewie banter.
The sequence is juggling a lot of stuff. Kind of a microcosm of what the entire film has to do.
The bigger problem I have is the big convenience of the Falcon just happening to be on Jakku so Rey and Finn could take it and Han could then find them. That seems a bit inelegant a way to get Han into the picture (and it's bit hard at this point to see if there's more to this that's been unrevealed or it's just general Star Wars level convenience where the galaxy is simultaneously vast and absurdly small).
But if you just accept that that's kind of messy and move past the how and why of Han getting involved, I don't really have a problem with how the story progresses once the Falcon is aboard the freighter. It's already getting to the point where I've watched the movie enough times that the story is just the story, and what happens happens. It just is The Force Awakens. I don't really have to dwell on the issues I have and can just enjoy the stuff about it I enjoy.
Also, I made this gif, which in my opinion is an A+ reaction gif: