HKIA and HK Immigration are pretty cool actually. There are several ways you can avoid the 30 minute immigration queue.

1) Select people (yes, I mean foreigners with no HK ID card) who are willing to give up their fingerprints can enroll for the e-channel. Enrollment desk is right after you clear immigration, sort of behind the immigration officer's booths, opposite the immigration supervisor's desk. Who qualifies ? Well it seems many airlines FF elite are eligible, I saw a promo a while ago suggesting this. When I spoke to immigration staff they kind of gave me the impression that anyone who visits HK frequently, regardless of airline status can enroll if you approach them.

2) HKIA themselves have a program for frequent visitors. This has nothing to do with the immigration department and doesn't give you access to the e-channel. To qualify you must have cleared HK immigration at least 3 times in the past 12 months and prove it by showing your entry stamps in your passport. You can then access a designated channel (usually the diplomatic / APEC cardholder channel) at immigration where I usually have, at best, 4 people in front of me. The bonus there is that (within reason) you can bring guests. I.e. your spouse and kids through the same channel.

You need to re-qualify every 2 years for this card. Theres no fee involved in either of these two schemes.

I will try to dig up some info and post more details shortly.