What to put in newly discovered rockery?

We moved into a new house a couple of years ago and inherited an overgrown garden. The job over winter involved getting rid of some self seeded conifers that had taken over the back garden. When they were gone and I was having a clean up I unearthed this rockery that has been hidden away for years!

As you can see, some dafs have already come back to life but what would you suggest to fill in the gaps between the stones to create an attractive looking centre piece of the garden?

Not fussed about year round colour and would be happy with something that came to life every spring/summer and then got pruned down in the back end to be dormant over the winter months.

It gets partial sun and I'm located in Yorkshire if that helps.

Thanks in advance!

Ignore the horrific state of the flags...had issues with the pressure washer

 

Basics would be Aubretia, Phlox subulata, Armeria, Alpine Dianthus (pinks) , Veronica, Cerastium tomentosum (can be a bit of a thug). Mossy saxifrage, Campanula carpatica, Lithospermum and autumn Gentian if the soil's acid or neutral,

 

Just wondering if it's a proper rockery (a pile of rocks with a soil in pockets of different depth and size) or it's a soil bank with some slabs of rock on it.
There are some small Aquilegia that will do well in a rockery, Sempervivum are good, lots of different ones available, if it gets a good dose of sun helianthemums will do well, as will Zauschneria. Then there are small erodiums and small perennial geraniums, crocuses, small alliums can do well.

 

I'd wait and see what comes up first.
If it full of weeds and weed seeds I'd glyphosate it in a couple of months before even thinking of planting anything new.

 

Following Nigel's mention of Aquilegia, this one below is a dwarf type called 'Rhubarb and Custard'.





I also I have this ground cover plant that flowers from late May/early June. It's shallow rooted, so easy to pull out if it spreads too much.

Chiastophyllum Oppositifolium.

 

Thanks everyone, that's given me plenty to chew on. And good point RE leaving it for a couple of months to see what comes up!