Gosh... so many options lupins, delphiniums, canterbury bells, hostas, hollihocks, buddlea, spring and summer flowering bulbs of course, aubretia and otehr low (ground covering) perennials... lucky you a new canvas to play with :-)

You could also try bergamot, ox -eye daisy golden marguerite, dill, the field poppy, field scabious, poached egg plant, honeysuckle, lavender, heliotrope, and probably less attractive for insects but good for winter colour interest, hardy carnations/dianthus and various euphorbia species.

Don't forget candytuff and wallflowers for the moths and foxgloves

Word of warning re Bergamot - I have monarda didyama & it has spread prodigiously if it's happy! I don't mind personally.
The foliage has a wonderful scent.