Suit yourself, but if you think it's safe to ride the wrong way, even in the situation you described, you're probably mistaken.
How do you not encounter any cars? As you're riding the wrong way, are there no driveways to your left? If a car pulls out of there the driver is likely looking to his left - where traffic is coming from - not to his right where there is no traffic (except for you).
And what happens when you reach the intersection? Do you go straight ahead and then turn left (on the correct/right side of that street), or do you turn left and stay on the left/wrong side?
Riding the left shoulder where there are no cars is preferable to crossing a right-turn lane and two lanes of 50MPH traffic through a large double intersection to get to the left turn lane for my left turn at the second half of the intersection. After that left turn I'd need to get onto the protected left shoulder/sidewalk of the next road anyway since there is no right shoulder on that narrow rolling road and extremely poor sightlines with very fast downhill traffic that makes it totally unsafe on a bike IMO.
I'm fascinated by the language with which you describe this traffic situation. Are you aware that yours is the language of cyclist inferiority thinking? That is, it reveals the underlying belief, perhaps subconscious, that cyclists have lesser rights on the roads than do motorists. Don't worry, most cyclists think the same as you. Look at the words you choose to describe what you have to do to get to a left turn lane: "
crossing a right-turn lane and two lanes of 50MPH traffic" Crossing? What, perpendicularly? Like a pedestrian jay-walker? Yes, that would be risking your life. You need to learn how to safely
merge vehicularly, not
cross, one lane at a time, negotiating for and establishing the right-of-way in each lane before merging into it.
Start out riding along the right side. Prepare for the left merge well before the right turn lane appears (I don't know how long it is, but usually if there is a right turn lane, by the time it appears it's too late to start preparing to merge across two lanes to get into the left turn lane). First, make sure you're not riding right alongside the curb or edge of the roadway. That's never safe. Then look behind you over your left shoulder, be careful to keep the bike going straight ahead (you might have to practice this). Looking back is usually enough to signal to a motorist that you are looking to merge left, but sometimes sticking out your left arm helps. Usually the first car will slow and let you in, but sometimes you have to wait a few cars. As soon as one slows - the driver may also wave or nod with his head - move fully into that line, about as far as the "left tire track", then repeat the process: look back, stick out your arm, wait until someone slows in the next lane and grants you the right-of-way, merge left. Note that through that step, the driver behind you is "blocking" - running interference for you, in your lane. Once you get into the second lane, you only have to do it one more time to get into the left turn lane. This technique works great even on roads with 3-4 lanes going in the same direction with 50+ MPH traffic. It seems crazy at first, but like anything else, once you do it a few times it seems perfectly natural.
As to the downhill with no shoulder and poor sightlines - take the lane! Imagine you are a tractor or some kind of heavy machinery requiring those behind you to wait. If you ride too close to the edge, you are
inviting them to pass you within the lane - not safe! If it's not safe to ride there, don't! Move out into the lane and make those behind you slow down, just as they would for the tractor. By moving out into the right tire track, or even the middle of the lane, your positioning and body language is saying, "I have as much right to this road as do you. You have to slow down; to pass me you have to at least partially cross over into the oncoming lane". Once a motorist realizes that he can't pass you within the lane, but has to cross that stripe to pass you, he will be leave much more room when he passes you. Also, even if there is no one behind you, by riding in the middle of the lane motorists in oncoming traffic who are considering passing (by moving into your lane) are much more likely to see you (and wait to pass when you're no longer in the way). Try it; you'll be amazed at what dramatic effects YOU can have on traffic through subtle changes in your lane positioning choices.
As there are roads upon which you refuse to ride, you really should look into improving your skills, and understanding and attitude about traffic cycling. Experienced cyclists skilled in cycling in the vehicular manner can travel very safely on any road designed for vehicular travel.
Serge