This stage is extremely straightforward, it's more of an exercise in mashing than anything else. It's also very RNG heavy with the bee behavior, ship movement, and vile behavior.
First half[]
Megaman X NO lag intro stage akka "all the tacos strat"
Killing all of the laggy enemies, "all the tacos"
To minimize lag from the flying enemies smashing the highway, it's easiest to kill the first 8 of them you encounter. It's possible to kill every single one of them if your mashing is good enough, though, and that saves on all of the lag.
There is a visual cue you can use for when to start shooting at the second and third blue guys, just to the left of the foreground posts.
Start shooting around here to hit the blue guys from as early as possible
Bees[]
The bee minibosses can be handled a couple different ways, most people go with a method that involves being hit twice per bee. This can work out poorly given bad bee behavior, if neither of them shoots at you, then the 4 bonks against the bodies of the bees are enough to kill you outright, so usually people will just reset if they get bad behavior. The good part about getting hit twice per bee, though, is that it drops your health low enough to trigger the vile cutscene (without needing to get hit by cars later on), and it also allows you to do double mashing (using both thumbs to mash the shoot button) since you can simply stand in one spot for most of the battle with the bee.
An alternate way to fight the minibosses is to pause briefly in front of the bees before taking a hit, this allows you to walk entirely through the bee and only take 1 hit overall. There's no risk of death in doing this, but it gets a bit complicated if the bee you're fighting shoots a missile at you, since those block your shots. The advantage is that you save on the 30 frames of hitstun from one of the hits, but you lose the ability to doublemash for any appreciable amount of time, so if you already have decent mashing, or can't doublemash, one bonk bees can be a good way to go.
Second half[]
The platforming after the bees is simple. No high-health enemies or anything, just run to the right and jump, shoot stuff that gets in your way a few times. On the large downward slope after the section with crumbling pieces of the highway, do a slope jump at the bottom. It only saves a couple frames but it's entirely free so there's no reason not to.
Jumping over this patch of ground avoids a drop and causes the second set of flyers to miss you when you're walking
On the platform before the cars, 4 flying enemies will come down at you. You only need to kill the first two, unless the second one drops health. Then you'll need to jump over it to dodge, unless you want to grab it and do TAS cars in the next section. If you do a full height jump before the second set of flyers spawn, they won't reach low enough to hit you as you walk underneath.
TAS cars[]
Tascars through end of intro
TAS cars through end of intro
If you have 4 or more hp after bees, then you can attempt TAScars, which can save up to about a second. Essentially what you do is allow the first car to pass you, then kill the driver and pop yourself up on top of the car so you can walk across the length of it, then repeat the process on the second car.
To get into specifics, when you encounter the cars on the platforms they spawn on, shoot them each with 4 uncharged shots and jump over them. Then, after jumping down to the lower section of the highway, get shot by the front car as it approaches you, after you get off your invincibility frames jump and shoot at the same time. This will get you on top of the front car. Walk to the front of the car then jump forward, you should land on the front of the second car and get hit, wait until the second car's driver is about to face forward again, which indicates he's going to turn his car around, and fire an uncharged shot. This will get you on top of the second car, which you can then walk across. If you have 3 health at this point, wait until the trigger for the ship is coming up before walking off in front of the car, otherwise just stand on the edge of the car and wait.
You can also shoot the first car with 2 uncharged shots initially, then shoot the second car with 4. This means you have to shoot the front car 3 times later, but it seems to be about equivalent on time save anyway. Do whichever you find easier.
Ship and Vile[]
To minimize risk of the ship going AWOL on you, wait a little to the right of the second phone box for the first car to drop out of the ship, kill it, then run all the way to the right. Once you reach the edge of the screen, turn left and kill the car, a good amount of the time the ship will stay put by the edge, allowing you to get into position under the wing. The ship moves extremely slowly after you've killed the cars, so it's far better to be in position ahead of time.
When Vile shoots at you, you can face left right before getting hit by the trapping shot and get knocked to the right, toward Vile, instead of backwards.