Here's a video that someone got me to watch today. It may help you. While I don't agree with some of what he says, a lot of the things that he says makes sense.
https://www.youtube.com/watch?v=nZeWOAliA6Y
how do you suggest I "get in there and learn the craft"?
You stop planning and you do it.
^^^ This
The thing about film making... there are many paths to entry, each depends on where you want to be, where you are and who you are.
One thing I'm going to say. There are so many people out there making films that have much less of a clue than you, who are as dumb as two rocks and have way less resources than you. You can do it once you choose to take the first step.
Make that first short film.
I'd suggest a slight alteration. Change that from a short film to a single scene. Write a 2 page scene, that is in one location, don't worry about acts, don't worry about an introduction, ending etc, just do a single scene. Shoot with a camera phone if you have to. Go to the local hardware and buy those crappy lights (or hell, just use the house lights) and shoot something. Don't have actors? Who cares? Grab some colleagues from work, go into the lunch room and shoot a scene you love from a movie.
The advantage of shooting a scene over an entire short is your learning curve is sped up. While it won't help you learn the craft of writing, it'll help you learn the film making craft.
From that shoot, work out what you can improve and improve one or two aspects. Shoot again... repeat until you're at the point where you're happy with the result where you're ready to shoot your sci-fi production.
Without the experience, I suspect you're having what's called analysis paralysis. You've got all this information and you just simply don't know which conflicting opinion is correct. I hate to be the one to say, most opinions are correct. It sucks I know. You need to work out which works best for you. You might even be at the point where you realize you need to know a lot more but you simply don't know what you don't know, let alone being able to work out what you need to know.
What I suggest above is going to be your cheapest way to learn and get into the process. What I fear may happen if you try the producer only angle is you may end up partnering with the wrong people who are more than happy to take your money, line their own pockets with a paying gig without a care in the world to whether you end up with a quality marketable product in the end. You may burn through all your resources and you may not be in a position to determine whether they're doing a great job or taking you for a ride. It's scary. It happened to a local producer here. He dropped a decent spread of his own cash. I don't remember the number but if memory serves me right, it was about 500k. They got a B name and all and he ended getting stiffed in the end.
If you want to learn low-range producing, I can point you in the way of a course/resource where you'll probably learn better than anywhere else (except by being taught hands-on by a real producer). It'll give you an idea of one possible path to becoming a successful producer. One problem you're going to encounter unless you're willing to drop $250k (or more) of your own personal money is: Chicken or the egg. You'll work our what I mean as time passes but you need to take that first step.
I offered h44 a while back when he was having problems getting experience. He said he had about $20k to $30k to drop on a film. I offered him to come here and I'd put together my crew, find a cast and shoot a no budget film within that budget and he could come here and learn anything he wanted. I even have a script that fits that bill (though the option will expire later this year). It wouldn't be a great film by any standard, but it's be a B feature film and it'd get completed and it'd be a good learning curve. Perhaps you need to find something like that.