These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
One in the sequel requires you to avoid powerups for a while. The annoying thing about it is that powerups placed over holes are unavoidable.
"Jackpot" in the sequel requires you to collect 5 gems in one playthrough. As gems randomly appear instead of powerups, you won't see them often. When they do appear, you might not be in a condition to notice.
One can make this easier by setting the powerup gauge to give out two gems when filled, but even then it can be rather hard to stay on top of while paying attention to everything else, due to the fact that you have to manually select the powerup instead of automatically receiving it when the meter fills.
Finally, the last achievements in the sequel require you to get a million coins and run 10 million meters.