I’m looking for comments and opinions on the best way to achieve R-25 or higher in a conventionally framed wall. I’m not interested in using SIPs.

Also what is the benefit of moving from R-19 to R-25 relative to thoroughly addressing air leakage? I’ve had several people tell me to invest my efforts in controling air infiltration rather than trying to squeeze in a few more “Rs”.

Thanks for your help.