out of your list I've bred flapnecks and oustalets and kept verucosus.
Verucosus are best for really advanced keepers IMO. I found it difficult to get a pair where both individuals were healthy.
Flapnecks are good, but again, sometimes hard to find healthy animals. Not impossible though. If you can find captive hatched or captive bred they are easy. If not, wild lifespan is pretty short (couple years or less) and the clock is ticking for most wild caught adults. Worth it if you are trying to breed them and/or don't mind the expense of veterinary assistance getting them cleaned up after purchase so they have a better shot at a nice long life in your terraria. Also, delipis has a wide natural distibution and sometimes comes into the pet trade in various locales that are particularly nice- similar to panther chameleons. Either the throat is particularly bright or unusually colored, or the flaps are little larger or the green is a bit brighter or the body is a bit larger or smaller, depending on where they come from- which as far as I know is a bit of luck and they haven't been mapped out like say panthers where you can just pick the locale you want.
Senegals, like flapnecks, are cheap, but senegals more often are heavily parasitized and sick and they also have a very short natural lifespan, so the clock for most of them is definately ticking when they are purchased- moreso than the flapnecks. I really don't recommend them unless you can get a rare captive hatched, or unless you are serious about trying to establish a captive population.
But my favorite on your list are the oustalets. Males grow huge- one of the largest and heaviest chameleons, are easy like panthers and veileds, and have incredible scalation that just make them look awesome- like fantasy dragons or trolls or something. They tend to have really great personalities as well. They aren't the most brightly colored, but the subtle coloring they do have is amazing up close and the detail gives the scales on their head some "pop".
So, that's what I'd recommend - oustalets if you can spare the space for a large cage and the insects for a large appetite- you will get a large personality in return.
