Dugan said:
As a final caveat: please remember that the bulk of your time with this dog will not be spent hiking. As much as we all love it, most of us have jobs that require us being home a significant amount of time to support the hiking habit. It's more important to get a dog that you can live with than one you can hike with.
Dittos on that statement! And all the other points made by Dugan.
70-80 degrees for dogs is HOT especially when the sun is beating down on them when they are active, running about, even playing hard in the yard. I haven't had one yet that I didn't have to watch closely for overheating in the summer. Some didn't know enough to quit.
How about a small pooch from a shelter? My mongrel was 35lbs, mix beagle and schnauzer mix???, and could run 30 miles to my hiking 10.
I had to put bells on him because he was such a lunatic out in the woods. I worried he would "get lost". It never happened and he saved me a few times when I got off trails. He did shed and loved to bark.No one's perfect. He was a great lap dog!
I agree that I think it will be difficult to find a dog that meets all your criteria.
Even at 35 lbs, my guy (Ben) walked and ran with me at least 5 miles per day. I really believe dogs needs lots of exercise, or you pay the price at home. They can develop lots of neurotic problems, not to mention destroy your home while you are at work if they don't get what they need. I often think this is why small dogs can be so hyper and obnoxious. If you had to sit or be carried wearing pompoms all day you might have anxiety issues to.
Corgies are nice dogs, short legs so you might have to help them over rocks, but I talked to someone recently who said his was a very good hiker. They do shed.
Any dog can be a lap dog. My Bernese is one and he's 120 lbs. He can never be close enough.
How about something like a mini schnauzer? I hear they can be stubborn but then again all of mine have met that criteria. Good training really helps with the problem.
You are going to have to get to know your pup well and there are no guarantees. It's like having a kid who you would love to have play pro-ball and he comes to you and says, "dad, I hate competitive games, I want to play the flute or be a writer. Leave me be and let me read".
Your little dog may hate to walk more than a mile or he might want to go 10.
You won't know until he moves in and really becomes part of your pack.
Good luck with your search. I look forward to hearing what you come up with.