I'll take a stab at the I-95 corridor since I use that to get back to NJ to visit family; in rough order north to south
Northeast
JFK
BelAir
Golden Ring
Glen Burnie (the Annapolis barracks has been closed for about 2 years now; why we still have them in the database I don't know...)
Waterloo
College Park
Forestville
Rockville
The JFK barracks are echo'ed on the State Highway 151.04 transmitter - however it frequently sounds like c*** due to over-deviation (whoever maintains that transmitter ought to have his fingers fried on the finals!). The PL is 173.8
The VHF lo band transmitters are not repeaters, so they can be very hard to hear unless you have a pretty decent mobile antenna. In some cases (not all) the barracks are repeated on the respective county's trunk system, as shown in the 2nd link I gave earlier. However there are places where that would be inaudible to you - the PG county trunk that repeats the College Park barracks are a case in point, since they almost exclusively use Phase 2 (which none of the Unidens can handle). We don't know if Cecil repeats their barracks because their trunk is unmonitorable.
There is a mention in the database that the radios now have the VTAC/VCall frequencies. I have rarely if ever heard them on there (perhaps they're reserved for heavy traffic days like Thanksgiving or emergencies), so I would assign them a low priority group. They are defined in our database here...
Interoperability Scanner Frequencies and Radio Frequency Reference
best regards...Mike