Cyrillic letters can be used to spice up English. Imagine having just one letter for "ch", "sh" and "th"!
"She relaxed in the chair under a tree's shade"
"Шe relaxed in фe чair under a tree's шade"
"She relaxed in the chair under a tree's shade"
"Шe relaxed in фe чair under a tree's шade"
https://old.reddit.com/r/conorthography/top/
Or you can take the plunge and make your own complete script:
https://old.reddit.com/r/neography/top/
And if you're still not satisfied and want to spend the rest of your life making a language that no one else will care to learn:
In fact, in Russian, at least, we don't have a "th" sound.
But this is better than using Д in place of "A".