What about stargates spawn on planets, but the player can craft the different chevrons to plug in, lets say theres 9 types(1 smartstack). Each address is a combo of 3 chevrons. And you can connect to each stargate provided you got enough powercoils.
These stargates spawn on the new worlds that expire too.
Stargate travel takes 1 oort shard(or x per distance) per person and the gate closes like warps do, after a minute or so.