@millercarbon has the right idea. Setup a budget first. Power is the foundation of your system. Start with the wall outlet at the beginning of the list. I would include either changing the power cord on the power conditioner or replace it. Furutech makes some products you could DIY the upgrade on the power conditioner. You could DIY all the power cords in your system with Furutech products. Link for DIY power cords https://www.youtube.com/watch?v=Ha6lakniW28
I know your conditioner, had one. Upgrading power cord was not to difficult. You may need new gromet depending on power cord you choose. It made a huge difference. You may want to upgrade some of the wiring while you have the box open. At the minimum change the connector on the end of the cord.