Few ideas i’ve done:
– Make “slider”, find the cloudiest scrumpy cider you can find and put the gin soaked sloes in their for a fortnight, makes a pink tinged toe-curler of a cider.
– Add the sloes to red wine, leave for a month (make sure there is no air gap at top), then after a month, remove the sloes and add a little brandy to taste, tastes like a half decent Port. (you can then make a very tasty mulled wine using this based on this recipe from Alexander Armstrong:
https://www.radiotimes.com/news/2013-12-19/alexander-armstrong-and-giles-corens-favourite-festive-tipples/ )
– I normally use freshly picked sloes, but have also used ones that have been in gin already to make Pacharan, a basque spirit. My version is about a kg of sloes, add a bottle of an aniseed based spirit like Annisette, Sambuca or Ouzo, 8-10 coffee beans and a vanilla pod, some people use a cinnamon stick instead of the coffee beans, leave for about 6 months.