That's why having all the trims away, before speakers assembly I'm going to put foams everywhere it's needed.
Door insulation isn't that bad - and for 10cm speakers it won't make big difference if you improve it.
The biggest issue I found in footwell - where behind front woofers there is steel w/o any dampening materials.
Also area behind seats it just thin partition wall - but in fact subwoofers are in closed boxes so any dampening materials would just make the vehicle a little bit more quiet, not improve the sound of subwoofers.