My answers will be based of the fact that you picked Primal-wow: 

• No. You can't enjoy exploring the world on an empty server. I mostly play solo too, but still: one of the most important things in wow (and MMOs) is seeing people running around, people doing random stuff. Going back to town or an Inn, and acctually finding people there (It feels like going to the bar at the end of a work day. You don't have to talk to anyone, but it feels nice to be around people). 

• Probably every single guild is recruiting. The server is so empty that they don't have the luxury to pick. 

• The point of gearing is to go for raids (or pvp, will talk about that next). So don't worry about gear because you won't use it for anything if you don't raid. Plus no one is doing dungons there. 

• The low population + The cross faction system (horde and allys can't attack each other and they are friends) makes it almost impossible to do any pvp. 

• Pick whatever you enjoy.