I feel the overgrown grass detracts from the overall appearance. You have some very nice shrubs planted there. I would consider a low maintenance ground cover such as Variegated Solomon's Seal.

Solomon's seal gets devastated by sawfly larvae most years, so looks dreadful by this time of year - perhaps this doesn't occur in the USA.

It depends on what look you want to achieve. Wild meadow that needs as trim once a year, manicured extension of the lawn or maybe a grass terrace?

If you want something low maintenance then move the shrubs, seed with native grass and wild flower mix, and plant swathes of crocus and daffodil bulbs.

A manicured extension of the lawn probably needs turfing in a lawn quality grass.

Terracing will take a bit digging to cut out but would allow you show off the shrubs.