I'm more PvP
oriented so I'll be commenting on your build for PvP, unless I specify otherwise. From what I can see, your build combines sniping with spiking. But, depending on what whether you chose Hwarang's Aura or Empress' Blessing, you'll want to go with either a spiking or sniping build. I assume that you chose Hwarang's Aura; if so, that means you should snipe.
This build involves the use of Beast Soul on your back-row while keeping your middle under constant HG via the Empress. The last time I checked the price of an Empress, she wasn't anywhere near 3.5B and Odysseus' Summon Papers can be purchased for well under 1B so those two are affordable for you. Assuming that you have Hwarang's Aura on your main, you can keep your Prophet. However, if you don't and don't plan to, you should replace her with a Hwarang to aid your sniping. The Cannoneer is there so that you have a full snipe line for Beast Soul and so that at least one of your snipers isn't shut down by a Princess. Also, you may consider replacing the LK with maybe a Guan Yu, or Valkyrie. Both of which I believe are under 3.5B. Hope that helps; feel free to argue some things or give more requirements that your perfect build should have.