This plugin has really helped in the scenario of testing client-server, or cloud applications where we want to lock a deployment across multiple test jobs, however we end up duplicating configuration between lockable resources and node.  A really useful improvement to lockable resources would be to choose the resource from online nodes in a pool represented by a node label.

For example, I currently configure:

• node label "BACKEND_POOL" representing a pool of Jenkins nodes where I can deploy my applcation back end/services
• lockable resources "SERVICE_POOL" with the identical list

Now I have a pipeline like pseudocode: 

stage("Build") {
    build()
}
RESOURCE = get lockable resource from SERVICE_POOL
stage ("Deploy") {
    node (RESOURCE) {
          deploy()
   }
stage ("Test1") {
   node ("Test") {
      Test1(server=RESOURCE)
   }
}
stage ("Test2") {
   node ("Test") {
       Test2 (server=RESOURCE)
   }
}

However, now I am maintaining the same list of resources in both the node label/pool and the lockable resource pool.  This leads to issues like nodes being locked for deployment even though they are offline, someone adding or deleting a resource from one pool but not the other, or someone taking a node offline in one place but not the other.

Lockable resources should be able to lock a resource from online nodes in a node pool, and keep it locked across multiple stages that require using that resource but not as a node.