[mkotowski]

> Also w for szcz makes no sense.

Propbably an attempt to use a letter similar to <Щ, щ> graphically.

> Why "x" instead of "z" in cz/sz/rz etc. sounds?

I think it is something picked up from Esperanto. Traditional way to replace Esperanto-specific letters, when not supported, was to change it to a letter followed by an “h”, but there is also a more widely used method using “x” instead.

[Tenoke]

Щ is already a pretty pointless letter. If you are simplifying anything then just using шт is one of the lowest hanging fruits.

Ditto for я and ю.

[hurflmurfl]

Щ is indeed read as "sht" in Bulgarian, but in Russian it would be read as a softer "sh" or mix between "sh" and "ch". If anything, maybe it can just be dropped in favour of plain "sh"?

[Mikeb85]

From Ukrainian it gets turned into "shch". Which IMO sounds about right. Mainly because sh and ch are shorter sounds in English (ch can also be a little hard), but shch gets the point across.

[int_19h]

This was also the historical Russian educated pronunciation; it only changed by the end of the 19th century.

Speaking as a Russian, I think that "shch" is close enough for an international conlang. It's not a sound that's particularly easy to learn or explain.

[Tenoke]

Just use sh where it is read as sh, sht where it means sht etc.

[hurflmurfl]

That's an option, but the big question is about "where it means sht".

Considering we're talking about constructed languages, whether "it's supposed to read `sh`" or "it's supposed to read `sht`" is defined by the author of the language.

On top of that, even coming to a conclusion on what it's supposed to read like means extrapolating it from present-day languages or from the now-dead languages. In a lot of cases, different languages will just have different readings. I.e. consider these words:

Group 1 - BG reads sht, RU reads shch

BG щипя - RU щипаю BG щастие - RU счастье BG ущърб - RU ущерб BG щит - RU щит BG вещ - RU вещь

Group 2 - BG reads sht, RU reads sht

BG нещо - RU нечто (Russian reads as "cht" here, but close enough) BG що - RU что (Russian reads "shto", at least in modern reading)

Group 3 - loaned words mostly try to mimic original

BG щора - RU штора BG поща - RU почта BG щанга - RU штанга

Plus there's the weird separate word [BG "sht" щателен - RU "tshch" тщательный].

Barring the loaned words from mostly Germanic origin, it looks like one language just sticks to "sht", while the other prefers "shch" and considers the "t" redundant. The interesting exception is the "що - что" pair, which is seems to preserve the T sound.

[wheelerof4te]

I propose we just read it as "shit" from now on :)

[ajuc]

> Propbably an attempt to use a letter similar to <Щ, щ> graphically.

Yes but then let's use R for "ja" :) This language seems like someone coming from cyrylic wanted to use latin letters, it's not good for Slavic languages that already used latin letters.