Hi OP,
I was never a chronic air hog--I sucked my share of gas though. So take my thoughts with a grain of salt.
I had the same issues as you; namely worrying about being a good group diver. I did not want to be the snicker bar in the punch bowl.
I do have HP 100 tanks. Bigger tanks are good.
May I assume you are a relatively new diver?
As others have stated regarding two issues, talk to the DM before you splash. Get his/her procedure and follow it.
Staying above the group really helps. Depth requires more psi.
Next, perfect your buoyancy and trim skills. Poor buoyancy and trim requires you to work hard which requires breathing lots of gas. Work, work, and work some more at figuring out your trim and proper weighting. Most new recreational divers are over weighted and not trim. Tank position can help with trim. Don't let the tank hang half way down your legs. Learn to rarely use your BCD. Learn how to release ALL of the air in your BC. Don't use your inflator hose to release air from you BCD as you will leave a bubble of air in your BC.
Remember, you should be horizontal with your knees bent and fins up--without finning or dog paddling. You should be able to hold that position without moving a muscle. You should be able to ascend slightly or descend slightly without using your arms or legs. (Of course, doing the above requires relatively benign conditions--being in a swirling turbulent current will make the above difficult)
As you experiment with weighting and trim, make notes in your log book. I have a matrix with every conceivable tank (AL80, Negative AL80, steel 85, HP100), all of my wetsuit configurations, and all my pony and sling bottle configurations. I use different weighting and trim for the different scenarios. For me it really makes a difference.
Before I depart on a SCUBA-great-adventure, I step up my fitness routine. I focus on increasing my vital capacity. A robust set of lungs solves lots of problems.
I am no longer an associate member of the Air Hog Club.
You many never be that person who gets back aboard with 1100, 1200, or 1300 psi, but you won't be the snicker bar in the punch bowl either. Some of us can hoover-down a tank in a few minutes if we wanted to. I am not 5'2" tall and 98 lbs. It is not really fair to compare me to a small person who has an AL80 same as I do. The world isn't fair.
May I assume that you are 6' plus and about 200 lbs +-?
I hope I presented my thoughts nicely. I am not trying to flame you.
markm