We always keep our luggage on the racks supplied in the rooms (if there is only one, politely ask if they can give you another luggage rack, they're usually happy to oblige). We hang our clothes in the closet, provided we check the hangers first and the clothes do not touch any of the surrounding walls in the closet (you can also bring your own hangers from home).
When you take an item of clothing out of your case, or put one back in, always zip or latch the suitcase shut (don't leave it sitting open or undone). This may seem like a hassle, but we do it on every trip and it's really not a big deal.
If you must use the dresser drawers, make sure to do a thorough inspection. We actually bring a small magnifier on vacation with us (we started doing this when we took my niece and nephew on vacation as they got slivers that were hard to get out without a magnifier), but they come in handy for inspecting the bed, frames, drawers, etc.
If you can bring some "rest easy" with you, it wouldn't hurt to spray the drawers first, as well as spraying the outside of your closed luggage. I personally wouldn't spray it inside my suitcase, but if you're really paranoid, it sounds like it's non-toxic and wouldn't be a problem.
We also leave a note for housekeeping telling them NOT to turn on the air conditioning. Bed bugs love the cold. We ony turn it on when we are actually in the room.
As far as bites, I think in the future I am going to invest in a lightweight pair of "full" pajamas (long-sleeved top and full length pants style) rather than nighties or the t-shirt and boxers my DH and I normally sleep in.
I'm hoping that little things will go a long way.
Tndislvr.... hope today has a little rainbow in it just for you