Correcting deformed mature shrubs?

Hello.

I recently moved into a new home and the garden has mature shrubs planted so closely together that it has created ugly clumps of mismatched shrubs competing for light.

I have removed the smaller shrubs to give the larger ones more space but they are so asymmetrical and patchy that i don't know how to fix it.

I have tried looking at pruning guides but cutting an 8ft red current bush, for example, full of flowers and buzzing with bees down to 50cm from the base is beyond my confidence and ability.

The red currant bush, however, is pretty much bare on the left and is very top heavy and i don't want to leave it like that...

There are several mature shrubs in similar states but i don't know what species they are - just that they tend to be very thorny :pala:
Where do i start?

Thanks

 

I think to give advice without some pictures or at least ID ing the shrubs concerned, would be a bit difficult.
Can you post some pictures?

 

leave them until the correct time for prunning, which in most cases is the autumn or early spring or just after flowering for early flowering shrubs.