You might consider leghorns. About the only criteria they don't meet is that they are not one of the bigger breeds, but they are more flighty than most of the larger breeds so they tend to be more aware of their surroundings and approaching predators. They are supposed to be excellent foragers, lay lots of eggs, and generally won't go broody on you (although there have been a few threads this year about broody leghorns, it's not that common as they are bred for production). I have read several people who say that leghorns are the only breed they haven't lost to predation when they free range, even the white ones. Plus they come in a couple of different colors (white and brown being the most common and best layers). And they do come in a rosecomb variety that is less prone to frostbite than the large single combs if you have severe/cold winters.
Of the breeds you have listed, welsummers would probably be the best bet. But, if you have the room, I would suggest using one of the breed selector tools to narrow down to the breeds that most fit what you are looking for and then get a few of each to see what you like best. Breed descriptions are a great place to start, but sometimes what you get is not quite what you expect from reading general descriptions. For example, although leghorns have a reputation for being very flighty (and therefor were on my list of breeds I didn't want), I did get one exchequer leghorn and she has turned out to be the least flighty bird in my small flock so far. After my initial concern that she would be a crazy chicken (I went ahead and got her anyway because I just fell in love with the color...figured if she turned out to be the type of bird that drove me batty I could easily enough find her another home) I wouldn't mind a whole flock of them and if I had the land to actually free range I would also consider other leghorn varieties.