heavy bombers reached their ceiling, i think with the b-52. developing new bombers, as far as i can see, is a criminal waste of resources, post Cold War.
The B-52 can be detected with COTS equipment by anyone who can solder and watch a Youtube video. The B-2 could not be detected by the most advanced radar equipment available to the time of its launch, and even today most equipment not fielded by or funded by Russia or the US could not detect it. Your mailbox key literally has a larger RCS than the B-2.
COTS = Commercial off the shelf (stuff you could pick up in a Radioshack before they became mini-Bestbuys, basically).
RCS = Radar Cross-section (a bit more field-specific, more or less how "big" the thing looks on radar, but it is a bit jargony -- it depends on things like the material and radar wavelength).
