Looks like three-starring everything in 150cc and Mirror Mode is going to be quite an adventure! I delved into the former today, and while I didn't lose a single Grand Prix, getting perfect 60s just went from "if you fail and Dolphin Shoals isn't involved, you have issues" to "get a lottery ticket if you manage to get it". I'm not joking. The AI is godly at slipstreaming and sniping you with green shells. Especially the former. While I'm not one to cry foul play every single time things don't go my way, I had a little incident on Yoshi Valley that suggests the AI is cheating when it comes to slipstreaming past you.
At one point the giant egg was pretty badly placed, so I drove past it, but couldn't get back on the normal racing line in time for the bridge, so I hit the fence. Then a fraction of a second later, Peach smacked into me! And I mean it, at the exact spot where I was - and I wasn't that close to the bridge either! It's the kind of amateur-hour stuff even 50cc AIs don't do. Sure, they're slow as fuck, but hell if I remember the last time I saw an AI run into the track's boundaries. (Actually, I do, they're easy to mess with at the jump in Mario Circuit 2 in the original, but that's not the point.) That definitely proves that they're programmed to follow you with the kind of surgical precision a human being would be hard-pressed to replicate. I can't help but think of all those games where you have to escort NPCs, but their AI is so bad that they can't just follow where you're going, they have to get stuck everywhere. Game companies who need the hand simply have to hire whoever programmed MK8's AIs, that'd be the end of one of the most frustrating things gamers have to put up with.
But that wasn't all I'd seen in that race regarding slipstreaming. During the final lap, I was leading at the hairpin that leads into the segment with the giant egg. Suddenly, I see not one, not two, but THREE AIs slipstream past me AT THE SAME TIME. I'm in the middle of a war zone, and just past the bridge I get hit with item after item, and finish SEVENTH. All I had to do was win this race on a track I'd always liked a lot, and the three stars were mine. NOPE.
I also realized just how early you need to start drifting for some of the sharper turns - even with the Yoshi Bike 3.25 handling can seem low sometimes. Bone-Dry Dunes in particular became a LOT harder in 150cc, especially one specific part. There's one area where you can choose between an anti-gravity area with spinners and a regular one with turn after turn, and I figure the former is the way to go. Well, if I trigger the speed boost when jumping off the end, somehow I can never land on the bridge part up top, and when I land at the bottom, I'm right at the next turn with no time to drift before I hit the outside wall. So I decided, that boost off the edge is a poisoned gift. I'm just going to drive off, float safely and land well before the turn, drift as much as humanly possible the moment I land. Of course there's probably a better way to do things (especially if I find a way to land on the top section), but for the time being that'll have to do.
So yeah, I've had my fair share of frustrations. Still, nothing forces me to three-star everything within a week, I'll get better with time, so I should stay calm. Besides, it's not like I managed the feat in previous games, though with the only criteria being winning all four races it's definitely more within my reach. I'd try competing against staff ghosts to help me learn the best ways through each level (and unlock a bunch of stamps in the process), but with the possibility of a complete leaderboard wipe if Nintendo chooses to fix the fire hopping exploit, I'd rather wait.
On a final note, the good news is that I still three-starred the Mushroom, Shell and Leaf Cups (the last one on a subsequent attempt), so I still have done some work.
Edit: I forgot to mention... I was kind of angry when I first found out the map was put on the Gamepad, with no option to have it on the screen. But with how complicated they can get with the anti-gravity segments, it'd be hard to make it work on the screen, so I can see why they did it the way they did. Still, there's an alternative I would've liked to see, and it's projecting the length of the track on a rectangle surrounding the screen like they did in MK64. You remember that, right? That was awesome! I wonder why they never even thought to bring it back, especially since it's such a great solution to the problems posed by MK8's track design...
Edit 2: Figured out the trick in Bone-Dry Dunes. What you want to do is go as far left as you can at the end of the anti-gravity part. This'll launch you from a lower altitude, so you'll hit the ground quicker, and if you start drifting the moment you do so you should make it. See? The key is to not despair, give up and switch to a featherweight out of disgust. It really pays off to practice and get good with a heavier character - the heavier the better, unless you're in an acceleration bracket that requires a regular heavyweight. Sure, you won't take turns quite as sharply as you would with a lighter character, but the huge difference in speed justifies getting good enough to compensate for the lower handling.
Edit 3: Or you can descend faster by pressing up on the analog stick. Didn't know you could do that. It would've saved me a lot of trouble if I did!