...Ignoring the resting requirement (I go out for up to 5 hours at a time and have never felt the need or desire to rest on my float). I would make 3 recommendations:
1. A cheap, single-skin, breath-filled torpedo shaped float with the appropriate diver-down flag for your location (Atlantis!), red and white for USA or blue and white alpha flag for most of the rest of the world. Such a float is small and light, great for lengthy walk-ins, less to carry and small boots/trunks. Good for vompetitions. Use self adhesive bike tyre patches or superglue to fix any leaks
Or
2. Big, cheap, Double-skin (i.e. bladder + cover) torpedo-shaped float, with flag as above. Takes longer to dry. Same advice for any bladder leaks, similar advantages.
Or
3. Flat, "plank"- style, double skin inflatible float, with flag as above and elastic mesh to hold a few extras above water (such as water-bottle, crocs, phone, crab bag, torch, etc.) and extra speargun (s) underneath. Avoid the very real temptation to carry a lot of unnecessary cr@p.
You will need to add ballast, such as lead, to all of the above to keep them and the dive flag upright.
FYI I used a #1 float for several years, works well. I currently use a #3 style float. Mine is a Picasso but I would recommend the similar Dessault product which flies an alpha flag. #2 style floats have intrigued me since I saw the late Peter Crawford (13 times British champion) using one at a competition in Devon.
Omer's dry bag float looks interesting.