Bogdans Afonins made several improvements to JOSM’s search and to the download dialog:

Search dialog

Search is incredibly powerful in JOSM. It’s possible to add buttons to the toolbar for searches you need over and over again. Some examples:

Select all ways of a roundabout or a closed oneway way, which is in view plus all the nodes of that roundabout that have more than 1 one way connecting to it:

R inview ((junction=roundabout OR closed  oneway=yes) OR ways:2- child (junction=roundabout OR closed oneway=yes))

I use this to make them round and distribute the nodes or to conveniently select all the ways of a roundabout after it was split.

Find all routes that are already public_transport:version=2, which have members in view and which were modified:

R "public_transport:version"=2 route=bus inview modified

Download dialog

The wizard works like in Overpass Turbo, but of course the output will be set to meta, so JOSM can digest it.

Some examples:

[out:xml][timeout:325][bbox:{{bbox}}];
(
  (
    node["highway"="bus_stop"];
    node["public_transport"="platform"]["train"!="yes"]["ferry"!="yes"];
    node["public_transport"="stop_position"]["train"!="yes"]["ferry"!="yes"];
  );
  ._;<;
  way["highway"="platform"];
  way["amenity"="shelter"];
  node["amenity"="shelter"];
  relation["route"="bus"];
);
(._;>;);
out meta;

This will download a skeleton of all bus routes in a the selected region. It’s a bit complicated, but sometimes it’s easier to go from complex to simple, by removing what is not needed for your use case.

Another one (now that I’m on a roll):

[out:xml][timeout:325][bbox:{{bbox}}];
    node["highway"="bus_stop"]["public_transport"!="platform"]->.allbusstopnodes;
    way["highway"];>;._->.allhighwaynodes;
    (.allbusstopnodes - .allhighwaynodes;);
out meta;

This stores all highway=bus_stop nodes in the selected bbox, which don’t have public_transport tags yet in a named container. Then it puts all highway nodes in another. Then it subtracts these, resulting in all highway=bus_stop nodes, which are not part of highway ways.