Which soft fruit bush

There are various varieties of blackberries, loganberries and Tayberrries so goggle them and see which has the sweeter taste. Many berries do need additional sugar depending on what you use them for, so have a look to see which suits you best.

If you don't have a dessert gooseberry, I can recommend Xenia.  Don't believe any descriptions that say thornless, but they don't have that many.  They are sweet enough to eat raw off the bush, but I cook them as well.

Another slightly different thing I have are 2 pink currant bushes.  They are also pretty sweet, but do have a little bite, so more flavour than white currants, but not anything like as sharp as red ones, so are more easy to use in puddings.

If you have room for some posts and wires, the hybrid berries are also very productive.  I have tayberry, loganberry and boysenberry and all are good.  Loganberries are the tartest.  Tayberries and boysenberries are sweet enough to eat without sugar.