If its design ideas you are after, I've made 2 recently. Adams looks better, mine were designed purely functionally. We have a big old traditional set which gets used several times a week, my son who has been living here for a few months and is a very good and keen cook moved out so I quickly made him one to take with him, at the same time I made an insert for our big one. The insert is just that, fits inside or you can hold it in your palm, if you are cooking for one or just want to grind a few peppercorns it saves the faff of washing the big one out. Included here just for interest really.
The main event is the larger sycamore one. I kept a full diameter base, you can hold it down with one hand for serious work and left a lot of 'weight' in. No pouring spout, might add one one day, but the slight undercut on the lip means you can pour over the edge without dripping. The beech pestle is aesthetically lacking, appears too big, but has a small end so you can see what you are doing if you just have a few spices. The big end curvature is such that there is no part of the bowl you can't reach to apply pressure. The main reason for the size is so you can get your whole hand around it comfortably for recalcitrant items. Finished with a wipe of canola/rapeseed oil and intended to be washed, scrubbed etc just like a chopping board. (yes, you can see the faceplate screw holes on the bottom, it's a kitchen tool )
It wouldn't fly off the shelf in a trendy craft shop, although it might with a prettier pestle, its built for everyday use - we often start with a garlic clove and a few fresh herbs and end up with a bowl full of salad dressing or a paste to start a soup.
So now you have 2 design approaches to think about.