You may have rejected catching a connecting flight in the US as too much hassle and too long a travel time. Catching connecting flights however, is very easy. As America is such a huge country and the airlines operate on a hub system, there are hundreds of thousands of people catching connections every day and the airlines and airports are arranged to facilitate this.
Catching a connecting flight can have a couple of advantages. As direct flights from the UK only go into a number of large hub airports, it can often make sense to catch a connecting flight to a smaller airport to avoid a very long drive. It can also be cost effective as often most of the price of your flight is the transatlantic part, so the additional cost of travelling onwards can be small. It can also sometimes be cheaper to catch a connecting flight even to an airport that is served by a direct connection. We have travelled to Miami via Chicago previously and saved a couple of hundred pounds.
In addition to giving access to parts of the US that would otherwise be out of reach, the other plus of a connecting flight is that you complete immigration and customs formalities at the hub airport where you land. You then switch into the American domestic system for your connecting flight and do not have to do this again. This means that the time between your flights is not all ‘dead time’, you will spend some of it completing the formalities that you would have had to go through anyway. This can make your total journey time shorter than it may appear at first glance.