The problem with the use of singlish is tied to the history of the nation. Most significantly the population is so emasculated by our continued rigidity that the evolution of singlish continues only through it's use as a joke language. Get someone to really speak everything in singlish, and you're likely to think the person is a retard. Get someone else in another country to do their colloquial english, and it's a different story. It's all down to how long this country has evolved.
There's also no real comparison with other patois of other countries. They mix the english language with their one single language, while in singapore, there is no one common language, like bengalese with english, jamaican with english. What we get is a mix from another language, like malay/chinese, and english, in the context of singpaore. It's more chinglish, malayglish, or indianlish, which together makes singlish. But, thanks to our speak english campaigns in the 70s 80s, which pushed the populace to adopt english as the main language, we get literal mandarin to english grammatical transliterations like "open" the light.
There's also a fragmentation of singlish along racial lines. Some words will not feature in chinese singlish / malay/ indian/ eurasian. etc.
a: eh you poondeh, why you off my amp?
b: Dei your time up liao mah ...what.
a: i was going to execute my super stroke 10 finger guitar tapping run.
b: zhun bo?
c: but a, you pcc too much riao, sure not kena one.
a: kena your head ah!
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As Singapore sets itself up for a second wave of foreigners and immigrants, you can bet there'll be further evolution of singlish, maybe further fragmentation. You can see some of that in places like hardwarezone's edmw, where the members take a more chinese slant to the whole written singlish thing, together with a ( like it or not ), the japanese kawaii fixation.