Since you mention your trees i'll widen this to 'fruit' rather than 'soft fruit'.
Also whether you do things now or autumn/next year depends largely on enthusiasm/money and whether you plan on using pot grown stuff or trying to source cuttings etc and where you get them from. Cheapo stuff from the likes of wilco tend only to be available early feb/march.
Your tree list didn't include: pears, apricots, peaches, medlar, fig, mirabelles and anything else I've forgotten. Since yu have raspberries I'll ignore all the jostaberry type crosses and blackberries.
How much room you dedicate to each type has to depend on what you like to eat or cook.
the remaining soft fruits.. three types currants, 3 types gooseberries, several varieties blueberries and add honeyberry, grape and passionfruit and kiwi into your thoughts
Personally I've never had much luck with kiwi - probably my failure. My wife likes passionfruit but i don't care for it and they dont do so well in my bit of wales.
In my opinion figs are a must..best thing ever is a fresh fig off the tree and cuttings area doddle to make lots more.
I also love blueberries and as example when we moved here and i had the builder in making a base for my large greenhouse i got him to use the digger and carve out several pits in my soft fruit patch (not in the greenhouse to avoid confusion) I filled with ericaeous soil and mixes i made up as a starting point for my blueberry plants - I'd brought several in pots with me.
I have 4 really well established full size blueberries and about a dozen yunger ones in assorted stages of development.. and that's not enough blueberries as far as i'm concerned whereas a couple fo mature gooseberry bushes does me. It takes at least a half dozen blackcurrant bushes to supply just me (OH doesn't like them much).. and this year I'm adding another dozen Red and white caurrants just get .. eaten off the bush. Honeyberries haven't matured yet I'm still eager to see what they're like Grapes.. well again personal choice... I can't be bothered with wine making so just dessert grapes her and preferably seedless but for some reason I have a soil or parasite problem where i tried planting 2 of them and they keep dying.. still trying to figure out why whereas 2 other vines are going good.
Finally ('cos its me) don't forget nuts - find somewhere to grow some nut trees.
And just as a final thought... if you really want to go mad you could just have a go at planting a date palm. They are more cold tolerant than folk think once establised although it'd take a lot of care for the first decade or so and many years before a crop..