With a small garden, nicely sheltered but lots in shade, I've found that "bush type" tomatoes (varieties like "Tumbling Tom" which can come in both red or yellow!) grow well in hanging baskets once they have sunshine and you keep them watered. I tend to add water retaining granules (I had a pack from B&Q, so hopefully I can find them again as I finished them off last year) to the compost when potting the basket initially. I buy the plants from the local garden centre.
I also grow "cordon" types (you pull off the side shoots and they grow taller) in large pots on the ground - I put 2 in a square pot that is 12" wide and support them with some bamboo canes.
If you have a sunny windowsill, try window basket pots on them. I usually put a small piece of wood underneath the tray to the front, to (at least mostly) counteract the slope of the windowsill.
Nice things on my windowledges have included:
Cut and come again lettuce (just pull a few outside leaves each day from each plant once they get going)
Spinach
Dwarf French beans
Radishes and spring onions
Dwarf peas (harder to get but there are varieties to buy as seed from Thompson and Morgan or Suttons)
Dwarf broad beans
Herbs
Baby carrots
I have a quite large round tub that I put more bamboo canes into and grow French beans up those - that can give us loads!!
Things like courgettes, single broccoli plants, broad beans, etc can all be grown in the middle of flowers. My one bed for veg has a mix of broad beans, courgettes, broccoli, radishes, spring onions, lettuces, beetroot and sometimes I squash in some summer squashes as well. All mixed up together.
The back of that bed, against the wooden fence, is a thick row of peas, supported along the fence, that almost disappears from your vision grown like that. And the flowers are nice, there's a (some kind of actual flower that climbs - DH is the flower man in our house!) purple thing at the end of that line, so the white pea flowers ending in the purple flowers looks nice and not at all "structured vegetable garden"-like.
I don't grow onions or garlic since I gave up my allotment, but it would be easy to add just a few in between things (but the amount to buy for seed is way too many for me so I don't bother - if you have someone to share a bag of onion sets or seed garlic with, it would be nice).
Some rhubarb in a corner is lovely, and takes very little minding but is really nice for those few weeks!
Strawberries in pots, hanging baskets, window boxes, or in the ground, all work well.
I have no currants anymore (since I gave up the allotment) but if I had space, I would put raspberries along a sunny fence and definitely some blackcurrants.