looks good, but just a point if I may...
most waistcoats have a smooth thinner fabric back for a few reasons, not least that any jacket worn with it will need to be able to glide over and woollen cloth isn't very good for that, and another reason to use thinner fabric is one of warmth, perhaps too much!
for posh wear with a jacket the shiny buttons probably work, but for casual something plainer, but you've already thought of that as they are removable!
Look forward to seeing more pics in due course!