Not sure what the problem with the connections are at Nottingham as there is normally at least 2 trains a hour on each line with generally a 30 min headway.
This is the problem with the connections at the Nottingham:
The hourly RHL train arrives in Nottingham at xx45 each hour.
Trains to the following destinations depart only hourly at these times each hour.
Lincoln/Grimsby xx34
Grantham/Peterborough/Norwich xx40
Manchester/Liverpool xx45
Grantham/Skegness xx46
Now that XC are only running hourly it is the xx41 departure to Birmingham which connects at Derby with trains to the SW.
You only have to consider all the places served by these trains listed above to see how journey times to so many destinations now include a wait of approx 1 hour in Nottingham.
It’s no better in the opposite direction.
The RHL train departs Nottingham at xx25. Trains from the following destinations arrive in Nottingham each hour at the following times again resulting in an hour added to journey times.
Skegness/Grantham xx20
Grimsby/Lincoln xx25
Norwich/Peterborough/Grantham xx31
Liverpool/Manchester xx34
Again the train from Birmingham/Derby which connects with the XC train from the SW arrives in Nottingham at around xx26
It was always the train to/from Mansfield Woodhouse, currently removed from the timetable, that passengers from RHL stations would use for connections. Not good for a town the size of Mansfield to be left with such poor links to so many parts of the country.