With a similar track record:
30+ years, hundreds of thousands of miles, half a dozen bikes, only one(!) accident early on which I could have avoided but wasn’t experienced enough yet
AND I ride like the devil! (>100mph whenever traffic allows)
So I’ll expand a little bit on the points below as different techniques apply at different skill levels.
But don’t ever ride when you’re tired or stupid.
Nothing to add here, same for cars.
This is true initially, but I actually look all around, all the time, and it’s saved my butt a couple of times, usually when some other biker or ricer decided they needed to race me and we’d split around a semi or other “obstacle” and I did not know they were there (yet).
I’ll add that “flow state” is very important at speed. If you ski, surf or snowboard you know there’s good and bad days, don’t even ride at all if you’re feeling out of sync. Or if you have to be really super careful/paranoid, (well, that’s always, but I mean 100%. 
My one accident was actually my third bike, got side-swiped by a guy coming through my blind-spot. (Before I was experienced enough to look everywhere, all the time!)
Some additional notes:
You will get pushed out of your lane at least once or twice (or more) a week if you ride a lot, don’t sweat it. Why not? Well, you always have an “escape route” or two, right? (Right?!?) Flow state FTW, you won’t even notice after awhile!
Assume you and your bike are invisible. Remember all the invisible man movies where he’s getting bumped into? Yep, that’s you! (Well, not really, but if you drive like it could be then you’ll be fine when in fact you are not seen.
Drive to be seen! Can’t emphasize this enough. You know that triangular blind spot every car has? (Going to be Ameri-centric here for a bit, you lefties know what to do). Stay to the right of your lane so the driver can see you in the mirror easily, as you pass switch to the left side of your lane so you cross the blind-spot as quickly as possible and maximize the distance between you. (Unless there’s somebody else right there in which case split the difference and go down the middle, but quickly, blip the throttle to keep your exposure to a minimum.) Does that mean you’re weaving a lot? Why yes! Yes it does! People visually “zone out” if they don’t see motion, YOU WANT TO BE SEEN!
Drive faster than the rest of traffic if at all possible. It cuts your bogey count almost in half and keeps you from being the zone-out case. Not crazy faster, don’t scare the little old people, and watch your “envelope” - that’s the space where you have to take evasive action if somebody enters it. And that means the right/left thing above changes depending on your speed. I.e. you just stay at the left if you’re going a lot faster than the folks you’re passing. (There’s a middle ground where I actually weave gently between left and middle.) As a general rule, <10mph faster full-lane weave, ~10-15mph faster half-lane weave, 20mph faster no weave, >20mph faster is stupid unless you can get over one more lane.
Maximize your envelope and DON’T EVER PANIC! If it’s a three lane road and you’re passing a guy in the slow lane, go all the way to the fast lane (if you can) to pass. You never know if they’re slow because they’re drunk/stoned/whatever. And be prepared to have no envelope at all. I’ve had one mirror scraping a wall and the other pressed in by somebody’s side window, at 70mph. (No shoulder and high-speed bumper-to-bumper - really hate that, chain-reactions are just nasty!)
But no accident (other than a scraped mirror) because I saw them moving into me and was already accelerating out of there to squeeze between him and the guy in front of me and because I didn’t panic. (Now if the guy in front of me had hit his brakes I’d have been sitting on the blind guy’s hood - lucky me!
Similarly with my one accident, I actually did see him coming into me at the last possible second and pulled that leg up super-fast so I didn’t get it pinned. We were going 45mph or so, but that simple action meant I ended up sitting on top of the bike as it went down and basically rode it like a sled until we finally hit a curb. (Yeah, it helps to be in good physical shape no matter how long you’ve been riding. Don’t get a bike that’s too heavy for you to lift from the ground while still astride, at slow speeds that “foot stomp” will save you countless times from oil, dead leaves, and spilled whatever.)
Your envelope is a simple equation of time, space, speed differential and riding conditions. If your shoulder is soft gravelly nasty shit, don’t include it in your “space I can escape to”. But don’t rule it out either. I’ve jumped a curb at 80, ducked under a sign and hopped right back into traffic without skipping a beat because at that moment in time that was my only possible escape route when another blind guy came sweeping across four lanes of traffic from the merge lane. Again, always look all around you, threats can come from any direction. It also helps to do some off-road riding even if just as part of your training so that you know how the bike is going to handle when you hit unexpected things. Besides intentionally jumping that curb I’ve also clipped cinder blocks, empty buckets, traffic cones, lumber, big chunks of tires, and once a cow skull, (somebody’s lost hood ornament?) etc etc, always in scenarios where I wasn’t able to see far enough ahead to spot it and it got hit or fell just right to shoot into my lane where I simply couldn’t avoid it completely. (You ride enough miles you get to see wierd shit, don’t let it kill you!)
On to riding ahead: always look as far ahead as you can, through, under, over, whatever, and get out from behind that big truck, (unless it’s really frickin cold and you’ll freeze. Look at other people’s tail lights, as far ahead as you can. That’s how you know about debris in the road, the guy with a bumper about to fall off, the trailer losing its load, and that hidden cop, well before you need to react. (In fact you shouldn’t need to “react”, because by the time you get there you should already be as far away as possible from that eddy current in the flow of traffic, and ready to move further if necessary!)
And do, always, wear appropriate gear. Even in the heat of summer I’ve got boots, jacket, full-faced helmet, gloves, etc. But I’m comfortable, because the jacket is designed for riding and well vented, and if I expect slow traffic I can open it and/or wear a “cool shirt” (funky material that you soak in water and it keeps you cool for hours at a time), and the gloves and helmet are also well vented. If I can go even 10mph I’m good!
As they say, “dress for the slide, not for the ride.”
