A couple different ways to shape high relief..
Rough cut needle files heated and bent to a slight curve work well with silver, gold, copper, ect.
Using a rough cut file to start with as they don't load up as easily,,and if they do they are much easier to clean out. Usually just a sideways swipe or two on a piece of rough cloth like your shop apron.
Also when the rough cut file is bent into a curve, the teeth will spread apart even more giving them a scraper type of effect. But you don't get the chatter like using a single edge tool as the other teeth even the cut and motion out.
Round & half rounds are your friends for smoothing details on 'chased' work which this really is. It's been cast instead of hammer&chiseled to shape,That's the only difference.
But tri-square and others are helpful too for line details.
Burnishing will brighten the silver up to the highest polish you can get if your burnisher is polished that well.
Just small odd shaped steel tools made to fit the contours you need to polish.
The more you get into a high relief design with something like steel wool, polishing paper, ect,,the greater chance there is of rounding off any sharp line contrast you've already worked to accomplish.
Very careful work with shaped polishing sticks, ect is used,,but carefully is the word.
When doing this type of work on steel hi relief, stones can be used effectively.
We used to use some call 'Water of Ayr' & 'Tam 'O Shanter' (sp?). I think they were a natural stone.
They were somewhat soft and quickly shaped themselves to area you were polishing.
Used w/water as a lube they were messy to use but worked well.
I never used them on gold or silver inlays. They just loaded up w/the soft metal then you had to pick it off the surface to continue.
Maybe something else is around like a modern ceramic stone that'd work. I should exit the early/mid 20th Century sometime and maybe take a peek at what they're using now.
Much of the high relief work detail can be done with punches also. Both smooth and surfaced tectured and of different face contours to shape the metal to your liking.
Once roughed out w/hammer & chisel you are at the same point that the casting here presents.
From there the punches form the piece to its final shape and finish. Very little final polishing, stones, ect is done after that in such work.
What ever the method,, it's easier and even better for contrast to leave the deeper cuts a little less polished and then give the standing edges and areas the higher polish.
Great contrast effect and once Ma' nature takes over with some tarnish in those deeper cuts on the silver they'll look even better.
Some very low and hard to get at areas can be lightly stippled too. No law against tarting the thing up with a bit of stippling, punch dots (don't over do it!) or even a few engraved lines to define things
Normal handling will keep the high-lights burnished bright and your finish work will look fine as long as you have kept the lines as smooth flowing and crisp as possible.
Just some thoughts.