I think there's a fine line between patriotism and just plain bad pronunciation, diction and enunciation. You may notice that even some British acts will pronounce certain words in a song the American way (e.g. some of them will sing "wanna" instead of "want to"), NOT because they're trying to be American, but simply because it sounds better that way.
There has to be a certain flow with words when singing, and choppy bad enunciation and diction just ruins a song.
Personally, I don't believe a strong Singaporean accent is appropriate in most music (note the word "most", I'm not saying this applies to all... it depends) but that is my opinion. I much prefer to hear what has come to be termed a "neutral accent". Also, I don't believe I am being unpatriotic by having this opinion. I simply have a respect for language, as well as a preference for singing that is universally comprehensible.
This is not just about Singlish or the Singaporean accent. Or even English for that matter. I get irritated by French Canadian singers who have too thick a French accent when they sing English songs. And I can't speak for other races, but I know alot of Chinese people who bitch about singers in the Mandarin/Cantonese music industry who can't pronounce their words accurately and with the right inflections. Yet, I've noticed many of these individuals are the very same ones who like to complain that Singaporean accents should be more accepted in music. Kind of hypocritical in my opinion. I don't really buy into these double standards.
My view is that whatever language someone sings in, they should be respectful of that language and try their best to be accurate in their pronunciation, enunciation and diction. If Singaporean English-language music wants to break into the international market, being understood is an important factor. No matter how "cute" or "exotic" some non-Singaporeans might think the accent is, chances are, it irritates the hell out of 80% of the rest of them because they don't understand what the person is saying.
I live in Australia and the majority of my friends here are Australian. I speak to them in a neutral accent and have never had any communication problems. However, I can tell you that almost everyone I meet tells me they are relieved I speak proper English coz most other Singaporeans they encounter (in their words) "speak really badly" and they can't understand alot of what they're saying. Either that or, they'll tell me some Asians will try and put on an American, Australian or British accent but it just makes it worse, especially if their pronunciation is bad to begin with.
Basically, what I'm trying to say is respect the language, but don't fake it.
It's one thing for a country to have it's own identity and way of talking, but to have so many people in a country NOT be able to spell and speak the language of instruction properly when required to... that's just ridiculous and has nothing to do with patriotism. If someone was patriotic, they'd want to give others a better impression of their country and not allow others to think that the nation is too stupid to be able to master their own language of instruction. It's cool if someone wants to speak Singlish and with a heavy Singaporean accent or whatever... but if they can't hold a conversation or SING in grammatically correct English with proper pronunciation when required, then it's kind of sad. Considering that the education system teaches every subject except the mother tongue in English.
Sorry if I'm sounding unpatriotic or whatever. That is not my intention or sentiment at all. I heard a New Zealand punk band play the other day and their Kiwi accent was so thick that it grated on my nerves. And if I were a Taiwanese, I'd also be bitching about how Australian vocal group, Human Nature (bless their beautiful pitch-perfect a capella singing), could have done a better job pronunciating their Mandarin words in "Mo Mo Ai Ni".
But once again, this is just my personal opinion.
I respect anyone else who has a different view.