Gut_man,
Congrats on your system! I have been in a similar path, mixing comercial products with mods to the speakers. I have lots of Duelund Cast caps and inductions in my external crossovers, they provided a great upgrade.
In terms of resistors, I recently replaced the Duelund Cast, with Path Audio resistors and my system reached a new level, so you may want to try them.
Cheers,
VPN