Well, I can't help but believe unless you're either artificial from the waist down or superhuman you're going to want something to keep your hoo-haa's and ho-ho's from freezing. :think: The water won't warm up enough for bare legs and whatever else til summer...congrats on the tube! Be safe.
I have been using my tube Summer and Winter. Even on the coldest days I find that neoprene waders (with layers worn underneath) keep me comfortable, and in the Summer heat they are perfect with just one layer (cotton) worn underneath. I think my waders are actually designed for hunting (they are camo-colored) but they were on sale at a great price at Sportsman's Warehouse.
not just to keep the dangling legs warm in these waters, but also to protect your legs. i was toob fishing with a buddy in sandy eggo bay and since the water's warm, he had no waders. consequently, when the tide carried in some icky yucky algae-like thingy, his legs were covered in slime, and he was scratching crazy when we got back to shore. he's fine after a trip to the medics.
point is, one never knows what the water will carry with it, so it's best to have waders. just my 2 cents...
Waders are a must IMHO. I prefer the dry waders as opposed to the neoprene. Good socks and long underwear and/or fleece you can handle (clear Lake) cold water in the winter for a good run. In the summer shorts only underneath will do nicely. I would recommend the socks waders over the boot attached waders- the boots wear out in the latter and your out boots and waders.
depends how high you sit on your toob... some are higher up, so hippies would work fine. some toobs dunk your butt deep in the drink, so you're gonna get wet from splash - in places you won't want to be wet... and water has a tendency to find their into those areas.
I don't know if it is a lack of coordination on my part, but I have a lot of trouble doing turns in place when out in my tube (a V-style Cat) using just my fins. I am going to be carrying a short length of paddle with me for those times when I need to manuever the tube quickly in order to cast to a certain point.
As far a propulsion for cruising though, I think you are stuck using the fin system.