For my own interest, what are the steps like out to the NW? It's been a while since I've been into PER from SIN but if the steps are similar to what they are coming in from the east then I'd be surprised if 9000' to 36 miles, 5000' to 22 and 4000' to 18 miles was going to be a drama at 'normal' descent speeds. Speeds above 300 knots may start to cause some dramas- particularly if your company SOPs allow that below 5000' AGL- but again, 'normal' descent speeds (250 below 10'000) shouldn't cause too many dramas?
What a/c type are you talking about Bloggs?