Looks like you got some good feedback on the Adult Learners group. A good shoulder rest helps to hold the violin securely without so much pressure from your chin. The center mounted chin rest would definitely help, too, from what I see and my experience. I actually quit playing for many years after playing for 8 years with an inadequate shoulder rest caused problems that limited my ability to progress with vibrato. It also caused me to develop a bad habit of raising my left shoulder to help hold the violin. Many other things contributed to my quitting, but the frustration from these problems caused by a poor shoulder rest was a big factor. I’m blessed to have
my music back and to be being healed of these old issues. God is good! Music can be healing, too.