I don't have a negative impression of the characters, but I don't really have a positive one either. Like the majority of elements in the film, they're... adequate; they serve their function in the story perfectly fine, but they themselves aren't humanized enough to trigger my empathy or hold my interest.
To rephrase, the characters and their actions make too much sense. What do I mean by that? Observe.
The mnemonic I would assign almost the entirety of The Force Awakens is "Linear"; it is EXACTLY what you would expect at almost every turn, to the point that I strongly suspect the film makers were deliberately playing into that expectation.
Basically everyone in the film, with the exception of Han Solo and Kylo Ren, behaves exactly like a generally reasonable, well adjusted person would given their situation.
Now I don't know if you've ever met a human being before, but they're not generally considered to be especially logical creatures. Oh sure, they can be practical, but the key difference is that logic is internally consistent; cyclical. Practicality merely employs logic for an ulterior motive, and while human beings put up a good front of consistency and reason, deep down, they're basically just exceptionally imaginative and insightful apes. They aren't DRIVEN by cold, solid reason, but by ethereal, paradoxical emotion.
A human being is the child of two colliding forces; one of instinct (What you want), and one of knowledge (What you believe to be true). And what we refer to as a "Personality", is defined and manifested by where and how these two forces intersect, conflict, cooperate, surrender, or dominate.
Therefore, the actions of one human being are not always going to make sense to another, who presumably has an entirely different relationship with both knowledge and instinct. In fact, let me ask you this; have you ever met ANYONE with whom you agreed with on everything? Of course not, anyone whose got their head wrapped around how this thing called life works knows that situation is so monumentally improbable that it's functionally impossible.
And the more you favor the side of instinct (What you want) in any given situation, the less logical sense your actions are going to make to an indifferent outsider.
Why does Rey turn away from every opportunity to leave that shitty planet? Because she wants her parents to come back. But her parents are almost certainly never going to come back, and she knows this. But she wants them to come back so badly that she's willing to sit there and wait for them based on nothing but the 1 in 1000 shot that they'll actually return.
This is one of the few instances in the film where a characters actions aren't perfectly neat and linear, and these are too few and far between.
Now the reverse of this situation is not good either; nobody wants to engage with a story in which all the characters are hysterical, impulsive psychotics with no grasp on rational thought. After all, humans are both reasonable and unreasonable; too much of either one and a character ceases to be human.
The Force Awakens is an example of of too much reason. Finn renounces the First Order because they massacre innocent people, a behavior that most all of us would also be vexed by. His decision to leave this clearly evil place is 100% reasonable... and because it's a decision that almost any sane person would make, it tells us absolutely nothing about him as an individual.
You could make the argument that this demonstrates his bravery, but the problem with that is that we're in an upbeat high fantasy story, and we know that Finn isn't going to get taken out of commission this early on. I can IMAGINE that this course of action is a risk, but I can feel it in my gut that Main Character Guy #7064(TM) is going to be fine, because I've seen him beat the odds over 7000 times.
This is the order of the day in The Force Awakens; just a bunch of reasonable, well adjusted human shaped aliens doing reasonable, well adjusted alien things, untroubled by irrational fears, impossible fantasies, unrealized dreams, or anything to do with that pesky "Humanity" thing.