Surprisingly for something which looks so exotic Aucubas were much planted in Victorian town gardens in the UK because of their toughness in areas with high coal smoke pollution. They were commonly, and innaccurately, known as 'spotted laurels'. The sexes are separate and some varieties are all one sex. If you have a female you might get red berries. But yours looks a bit like 'Crotonifolia' in which case I'm afraid it's a chap.

KDK6, It's a wax leaf privet. I have 3 of them. Don't allow your dog to eat any berries from shrubs, just to be on the safe side. I have a bichon too, and she is kept on a lead so she doesn't get in my gardens. They aren't high energy dogs. The privets do smell very good in April abd May when they flower. I use them for evergreen privacy.

Just the first few ideas that come to mind- probably many out there to put them all to shame: A dwarf Canadian Hemlock with variegation: 'Everitt Gold' or 'Cappy's Choice' come to mind. I'm pretty sure that the Full Moon Maple is hardier than the Japanese and there are colorful varieties of which 'Aureum' is the most commonly seen. Actinidia kolomikta 'Arctic Beauty' or Akebia trifoliata if you can support a vine. And lastly- since I've been on a bamboo buying spree- you might do some research on Fargesia 'Scabrida'. Its only leaf hardy to -10, but usually the canes and especially the rhizomes underground on a bamboo can survive colder temperatures as a dieback shrub. I would definitely encourage you to do your research- the bamboo forum is an excellent resource- but I thought I would mention it because of its great orange and purple components. Good Luck! Here is a link that might be useful: Fargesia 'Scabrida'

Lovely pot!! To some degree, what you choose will depend on what shape you want - tall and rigid, tall and flowing, short and round, short and weeping, etc. My two favorite choices would be: Spirea Ogon AKA mellow yellow, which is fountain shaped rather than the rounded or bun shape of many spireas. White flowers, fine willowy yellow to chartreuse summer foliage, and red-gold fall color. Clematis Stolwijk Gold, which has gold to chartreuse leaves and early blue flowers. Grown on a medium trellis I think this would look stunning. Ninebark I think will be too big for the pot based on my P. coppertina. I'm personally not a fan of privet and IME they get pretty huge also. Some other thoughts: Yellow oak leaf hydrangea, Little Honey, though it has a reputation for being a bit fussy. It likes at least part shade Yellow-variegated shrub dogwoods (Cornus), though they might be too large Yellow elderberries (Sambucus) might stay small enough in your pot though they get large in the ground Clumping bamboos, though I am not sure if any of the yellowish ones will be hardy enough for you. Yellow leaved evergreens, such as some of the Chamaecyparis, would have foliage year round if you will be leaving the pot outside. Some heathers have yellow to gold to orange foliage depending on the time of year and the variety. Caryopteris such as Sunshine Blue have gold foliage and late season blue flowers. You'd need to check if the flowers coordinated with the pot. Gold grasses, either variegated like some of the Miscanthus, or solid like gold Hakone grass. You might also want to consider a water garden in your pot with papyrus, though it wouldn't be hardy or yellow. Here is a link that might be useful: