@avery
Re 1. Hyphenated compound nouns linked by NG
tulisan ng dagat => tulisanG-dagat
bunga ng araw => bungaNG-araw
kwento ng barbero => kwentoNG-barbero
laro ng bata => laroNG-bata
The hyphen indicates that the 2 words are put together to form a 3rd word that derives its meaning from the 2 words, but in a slightly modified way.
For example, "bunga ng araw" is "fruit of the sun", but "bungang-araw" is "prickly heat" or "heat rash". Since "prickly heat" is the skin's reaction to sun heat and humidity, then "fruit of the sun" would be the figurative way of saying that. Our ancestors who formed the word most likely did not know the medical explanation for it yet, but since the phenomenon occurs during the summer months, only a figurative expression could be made. It's a word like "dog days".
"Kuwento ng barbero" is "a barber's story". As it is, the barber could be talking about what he had for breakfast that morning and that's just fine. However, when we say "kwentong-barbero", it becomes understood as a "cock and bull story". The basis of the allusion is that as a barber cuts your hair, he might concoct stories just to make them sound interesting and ease boredom.
These combinations result in words whose meanings are still close to the relationship made with the two words.
Re 2. Compound nouns with hyphen (without linkers)
Except for "bahay-bahayan", the rest of the words are formed by normally unrelated terms, but when put together, create a word with its own meaning. They are unrelated in the sense that linking or relating them with a "ng" or "na" would not give the intended meaning.
"Bahay ng aliwan" would be "the house where entertainment lives" and "bahay na aliwan" would be "house used for entertainment". I am not sure about the correctness of the "amusement house" translation as it might just be a euphemism, but what I know is that "bahay-aliwan" is like a honky-tonk place or a brothel.
"Bahay ng bakasyunan" (house of the vacation place) would not make sense, but "bahay na bakasyunan" would be a house for spending a vacation at. If I annually spend a week vacationing at my cousin's house, I may call it as "bahay na bakasyunan ko", but that does give it that my-little-cottage-in-the-woods kind of meaning; "bahay-bakasyunan ko" would.
"Anak na araw" (child that is a sun) does not make sense, but "anak ng araw" as "child of the sun" might allude to the brightness of the sun. It might be like "bunga ng araw". However, "bungang-araw" does have something to do with the sun, "anak-araw" does not.
Therefore, the meaning resulting from the combination may have some basis on the 2 words, but goes beyond that by having its own special meaning.
"Bahay-bahayan" falls under a different category. There are some Filipino words that are repeated with the "an" suffix on the second word. These are "pretend" words. They are always hyphenated.
bahay-bahayan = playhouse/play house
pera-perahan = play money
sakit-sakitan = pretending to be sick or malingering
iyak-iyakan = crocodile tears
kasal-kasalan = mock wedding
Re: 3. Compound nouns without hypen/linker
"Bahaghari" and "balikbayan", like "kapitbahay", are officially coined words. They are linked together permanently and considered as original words from the start.