I tried Hostas and never again. They are horrible to keep the slugs away from and anything near them gets the slugs also.
Ferns are nice. Hydrangeas, Rhododendron, Camelia, Elephants Ears (Bergenia - lots of different colourful types).
I tried sweet peas in the shady bit the last two years and they came up like giants. Even when the cold Autumn arrived, they still kept flowering, so just try anything and see what happens.
Bedding plants in April will really give a colourful show and all you have to do once planted is dead head them to encourage more blooms.
Lily bulbs are magical in my opinion throughout the summer months. If you plant them randomly, they pop up multiplied each year and all you have to do is cut off the dead leaves at the end of the season.
I have double tulip bulbs planted too, which come back multiplied each April and last until the summer plants bloom.
Have fun, spend as little as possible and if you see a plant you like whilst out and about with seeds, just nick a few and plant.
p.s. I have loads of pots, but you have to water faithfully even if it rains otherwise they dry out.