I agree with the reasons you like Bach and Chopin though - those are very good reasons to like their music, and you should read up on the harmony they use. It could definitely influence your own compositions if you do any of that.
Yiruma's stuff is harmonically simple - when compared to Chopin. His pieces though have instantly recognizable melodies which a lot of people today crave; this is not because they are simple minded people (or you would be against the massive majority of the population on earth), but just because they can tell what a beautiful melody is. I can assure you, a lot of the Ligeti Etudes do not have beautiful, singable melodies haha.
If you take any of the Nocturnes by Chopin, and just isolate the melody - they are all pretty simple, but since he wrote pretty much exclusively for piano, he had A LOT of practice to develop the complexity in his works.
Liszt has a LOT of pieces that are 'harmonically simple'... Check out Un Sospiro. There is very little dissonance in that piece, but it's masked because he was so proficient with his technique.
There's a complex that a lot of people have: if it's an easy piece, it better be dense as hell texturally/harmonically or it's bad. If it's a harmonically simple piece, it better be hard as hell to play, because then it's an acceptable piece.
Take the first page of the Liebestraum by Liszt (the famous one). What about it is so much different than some of the more New Age kind of piano music. It never veers far away from the home key.
Keep in mind too, music is something that is accessible if people are not able to take 'formal lessons'. A lot of people treat it like a hobby, and are really not interested in learning atonal music

Have you ever taken a second language in school? If so, did you pursue it to a master level, study the culture, read and memorize poetry, texts, etc? If you didn't, imagine someone who 'DID' calling your efforts boring and simple. But if you are fluent in the language, and can express yourself in a way that many people can see your intention, did you necessarily go wrong anywhere?
I know some people who do translation for a living from English -> French and vice versa; their accent may not be the best, but the work they do is solid and is appreciated by whoever seeks it.
In music there are 'levels', but seeing one ultimate level is a really 1-dimensional way of viewing something that can not be quantified.
Is something that took Chopin 10 hours to write necessarily 'better' than a song by Queen? How can either side begin to justify their views?
-Chopin's is harmonically more complex
-Chopin's is used for university juries
-Chopin's is more expressive
...
-Queen's uses deeply-layered vocal harmonies
-Queen's used professional studio recording techniques, mic techniques
-Queen's sold more copies
Crude example, but do you see my point? I personally play and listen to more classical music, but I can't imagine telling another musician that they are 'wrong' in what they listen to, or that their taste in music is garbage. They'd probably say the same to me if all I had on my iPod were Ligeti Etudes, Finnissy, Sorabji, and all other 20th century-onward music.