RivalCPvP is a CrystalPvP based SMP where survival and PvP go hand in hand. You get a free kit every 3 minutes, so it is easy to jump back into the action whether you are building up, fighting, or just messing around with other players.
The server also has an economy with spawners, which gives you a bit more to work with than plain survival. There is a 25000 x 25000 world border too, so the world has plenty of space to explore and settle into without feeling too cramped.