First off, a Llewellin is merely a particular line of English Setters. Richard Llewellin was good buddies with the founder of the Field Dog Stud Book (I forget his name) and Llewellin got him to register Llewellin's dogs as a separate breed. That foolishness went on for a few decades until the present where Llewellin's are now recognized as a line of English Setters that can trace their pedigree directly back to Llewellin's dogs.
That is an awful lot of dogs and one should not pay a premium for the Llewellin name. I've had two so called "Llewellins" and they were not any better nor any worse than the other ES dogs I've owned. My best two ESs were not Llewellins though the one probably had some in him based on looks. I wouldn't have bothered with the DNA test to prove its Llewellin heritage as it is meaningless.
As to which dog breed, that is a tough one. I prefer pointering breeds of one sort or another. My preference is for English Setters and the various wirehair breeds but I have owned maybe a dozen different pointing breeds as well as hunt over that many more.
Your best bet is to find a breeder that breeds for so called close ranging dogs. This will vary per breed per line and even dog but it is a start. A cooperative dog will adjust its range to the cover so "close working" can vary greatly depending on how far the dog can see and/or hear you.
I've owned flushers too, a pair of Springers as well as a half dozen Labs used as flushers. Plus an Aussie/Pitbull mix that is my current flusher. They really fit well with Minnesota's late season pheasant hunting habitat but flushers are just not my thing now that I am older. If you train so the dog will stop even when on a hot scent so you can catch up they aren't bad but few wish to put in the time to do so. My current flusher was the easiest to teach but it's breeding is toward obedience moreso than hunting.
I can't give you much advice on picking out a dog there other than look for the lighter built Labs for the uplands. They seem to have more endurance. And eat less leaving smaller messes. There are a number of heavy "duck dogs" in this region so finding an upland line can be a bit tougher. Also, look close to verify the spaniel is from field stock rather than bench. That applies to English Setters above also.
