During the first phase of the Ares fight is a fantastic place to grind out this trophy.
Once you get Ares health down you initiate the mini-game (QTE) where you stab Ares twice with his own spider-arm's. instead of completing the mini-game, only complete the first button prompt. You will gain about 3 levels of red orbs. Fail the second and Ares will throw you down and gain some health back. Smack him around again and repeat the method above as long as necessary.
Took me less than 10 minutes of this to have everything maxed out, but I only had a few things left to complete (Army of Hades and Blade of Artemis). Might take longer if you have more upgrades you need.