Akichi Daikashima said:
The parts of writing that I'm struggling the most are:
-Formulating a proper story around an idea
-Character establishment & development
First don't do those things in that order.
Coming up with a chain of events and then sticking characters on them is a recipe for disaster.
First setting. If for no better reason than to pick a consistent crop of characters for the story.
Second establish characters, but establish them for you (The audience doesn't need to know)
Wright up psych profiles for them.
What do they like, what do they hate, what's their backstory, what are they afraid of, how have they changed overtime before your story even started, what are their triggers (and why, always why), Do they have any previous relationships with other characters.
Just make sure you know them well enough to understand how they'll react to any given scenario.
That step is a lot of work and you're going to feel like you should include it in the story proper, but try to avoid that urge. It'll most likely come out as an exposition dump or a monolog (And there's no problem with those things, but if they don't move the story forward the run the risk of kicking the pacing in the balls)
They should primarily be used as reference for when you get stuck.
Third, with all the characters in mind, come up with a general idea of the plot. Then think of why each one of your characters would become involved.
And if you have a natural sense of pacing the story writes it's self from that point on.
Just find out when, chronologically, and where, geographically, all the characters would be at any given point in the story, and just make them interact with each other when they get there.
Drawing a rudimentary map to give you a good idea of how long it would take to get from location to location would also help.
Coming up with a general plot first is acceptable, but at least 3 or 4 of your characters need to be tailored to have extremely natural flowing reasons to want to move the plot in the direction you want.
Which in my opinion is harder than having well rounded characters and letting them write the story for you.
-Variation in descriptive sentences(I start way too many sentences with "The x was y")
That sounds like a blocking problem, why are you bothering me with it.[/condescendingly posh accent]
I write scripts mostly, so I can just skip a line and dedicate large sections to blocking with no real impact on how the lines get read.
If you're hell bent on writing a novel I'd suggest a co-author to help make your words more presentable.
I personally don't bother, I find people understand large dialog sections with bracketed off blocking easier.