large perennials for containers

How about hydrangea, Escallonia, Euonymus, a non-invasive bamboo and conifers?

Personally I wouldn't use bamboo in a pot. It's not the nicest looking plant on its own at the best of times, and is best used in conjunction with other plants in a bed. If you want a specimen plant for a large pot why not try one of the ornamental grasses, eg, Miscanthus Sinensis, Stipa tenuissima, or Hakonechloa macra Aureola. Or just one of the smaller clump-growing lavenders like Lavandula Hidcote or Munstead.

My mums front garden is just a south facing small concrete area and she gardens entirely in pots.  She has had great success with everything she has tried in them.  She has Roses, Camelias, Dahlias, Astrantia, Erysium, Iris's, Rudebeckia, Hellianium, Crocosmia, perennial geraniums, Alchemilla Mollis to name but a few and every type of bulb you can think of from Daffs, tulips in spring/early summer through to Lillies in the late summer and Narine's in the Autumn.  She lives on the sea front here and the tourists are always stopping to take photos.  Most of what she has she bought cheaply as very small plants at car boot sales etc. that way it isn't a big loss if they don't work out.  She uses a soil based compost in the pots and feeds/waters them all regularly.  Vine Weevle can be an issue.