Basically with gop video the way it works is that when you make an edit on a frame that is not the i frame FCP must create a new i frame when you render, export, conform to put to tape etc. That building of new i frames is what makes native HDV so processor intense and why it takes longer to render etc.
If you have drives that can handle the higher data rate and file sizes then go with prores.
There are no “technical solutions” to your “artistic problems”.
Don’t let technology get in the way of your creativity!