Queue is just the name of the letter "Q".

But it "kyoo" might not be an easy sound depending on your mother tongue

Schedule (sk- or sh-) differs between countries/regions. So you're good either way.

Subtle is spelled weird, but rhymes with muddle. Do you also pronounce "mad" and "mud" the same way? With my accent they have the same first vowel sounds as saddle and subtle

According to the Macmillan they are [ˈsʌt(ə)l] vs [ˈsæd(ə)l], so the vowel changes slightly, but it depends on the speaker; I'm not native but I say saddle with a more open "a". But they're otherwise almost identical to me (in the British pronunciation included in the dictionary I hear a "t" both times, in the American one a "d" both times - which is how I say it too)

I feel like a lot of people just drop the "I a" and say "'preciate it!", lol

(That's assuming you're using it like "thank you", and aren't just starting a sentence)