Great porch! I agree with you, the existing shrubs are hiding that lovely porch and from what you said about constant trimming, you may want to have them removed. Deciding on what to replace them with will depend on your preference of style. Do you like a more casual look such as Annabelle Hydrangas, the white flowering shrub in the first picture, or do you prefer a more traditional style, such as clipped boxwood, and globe cedars? The boxwood stays pretty compact after clipping and gives a more formal look, smaller lighter green perennials could be planted in front of them such as Hostas, which like north facing. A nice sweeping border edge from your walk way to curve around the end of the porch tree you already have add some mulch, possibly two large planters with some colorful annuals at both sides of the stairs will set off that beautiful porch. Your local garden center can suggest plantings suitable for your location. Be sure to bring along a picture.