It depends on what you want the hatchet to do, and the trip you are doing. I never bring a hatchet on a backpack hunt, but do bring a good folding camp saw that can be used for wood or bones. Silky makes some supurb saws that steel that holds up to rough use. Hatchets need some heft to effectively split wood, so there is a compromise when you reduce the size and weight. The axe or hatchet can be the most dangerous tool in camp as far as injuring yourself, and for that reason we totally ban their use on my summer canoe guiding trips. If you choose to bring one along, make sure it has a good sheath, and have a pair of leather gloves to wear while using it. I have put 18 stitches on myself from using hatchets, so it is a lesson learned the hard way.
I now have a collection of what may be the best hatchet/axes made, by Gransfors Bruk. They are hand forged in Sweden, and you pay accordingly. The Hunter's Axe has a 1 1/2# head and a 19" hickory handle. I faced down a charging black bear (bluff) while I had one in my hand, and had supreme confidence that I would have cleaved his skull if he got a few feet closer. I will be bringing one of their Scandinavian Forest Axes (2# head, 25" handle) on a 3 month canoe trip next summer, but we will need to do some major bushwacking along the way. A lighter option is an A.G. Russell ULU hatchet. It is lightweight, has good steel, and you can snub up on the handle to use the blade as an ULU.