Hi all, not posted on here for a while but been a member since the olden days so salutations all round!

So, need to improve the sounds in the family zafira b. ATM it's standard cd30 and standard speakers. I'm thinking decent components up front, maybe some coax in the back (or not bother) and a good quality double din HU up front. Needs iPhone or aux in and to maintain multi function display and steering wheel controls. It's a family car so volume not important but good SQ and dynamic range are desirable.
Don't know if it's worth filling doors with dynamat or adhesive flashing??

Any thoughts or advice appreciated