If you carry a lot of gear or prefer more room to stretch out, a two-man 2-person portable tent is a smart option. Moving up a size, it gets even more comfortable, but you may need a sled to move it.
The material of the shelter determines how well your shelter collects heat. Insulated shelters made of nylon or mixed fibres gather up the heat and keep it inside efficiently. In contrast, noninsulated shacks made of cloth and lighter denier fabric are much easier to carry, although they don't hold heat inside the tent.