I think you'd be better off with things like the coloured stemmed cornus planted in groups of contrasting colours. I have 4 and they all happily sucker or layer themselves along if I let them. There's the bright red of cornus alba siberica which has lovely spring green foliage that goe sto purples and reds in autumn. There's the fmae effect of Midwinter Fire, the burgundy of elegantissima which ahs variegated foliage and then the lime green of Cornus sericea 'Flaviramea'. All will need pruning back in spring to maintain the colourful stems but you could do them in alternate years or just take out a third of the old stems every year.
You could intersperse these shrubs with clumps of easy care grasses such as miscanthus which are hardy, come in various heights and will provide movement as they sway in the wind a well as food for birds in autumn.
Have a look also at spreading conifers and small trees for contrasts of colour and form. Clematis usually like something to scramble through rather than over bare ground. Kiftsgate rose definitely prefers to grow up things and has vicious thorns which would make trying to work around it very hard.