Hi Andrew and others.  Let’s start with the chin rest.  The main problem I see with people changing chin rests is that they use something too long to engage with post barrel so that it protrudes from the back of the hole and damages the rib varnish behind the post.  Often, the original chin rest was applied too soon to allow the original varnish is set and some of the cork remains engaged to the top or bottom plates.  I have no concern of this because I play cheap violins.  And make sure of clearance between the chin rest and the tailpiece to avoid buzzing.

The You Tube videos provided by Fiddlerman and Rosa String Works (among others) are excellent in explaining the process of making the necessary measurements to get the proper string height of a bridge and how to shape the bridge feet.  I found that it was much easier to use an inexpensive belt sander to reduce the depth of a bridge than to attack it with chisels (search for “belly” to find the thread where I discuss how to do it).  I would start with inexpensive Chinese bridges (I found that the Cinderella brand on eBay are very good) and fashion two at a time so that you use the best and keep the spare in the case for emergencies.  I would put a drop of superglue on the ebony insert of the Teller since it may come off during chisel/sanding otherwise.

You may want to look at my thread on roasting bridges since it is easily done and adds a good deal to the performance of the bridge.

I would advise learning how to make changes on you own instruments if they are not heirlooms.  I would wait a few days on working on the bridge since I am about to do an experiment for bocaholly on the use of a bungee cord clamp to retain the sound post.  I should have results by the end of the week.

I agree with bocaholly (as I always do).  The knotch in the bridge under the e string started its life as an ebony insert to protect the bridge from splitting via pressure from the thin string.  

If your chin is consistently over the tail piece as depicted in the photo, you should consider a flesch or similar chin rest.

I have seen one that was left mounted that projected just slightly beyond the center line of the tail piece that was much lower than the normal flesch.

Item I was thinking about appears to be a mis-marked Dresden chin rest.  Just received by mail a 1/2 sized flesch chin rest with about 3/16” material above hole for tail piece (Johnson String item chvnfflebst_3).  Certainly could be used on a 4/4 violin for someone with a small neck.