The best path is not always the most expensive one
Another good target for Seething Spirit is Ionos Kilowattrel, which can use its Flashing Draw Ability to discard a Energy from itself to draw until you have six cards in hand
Yavimaya, Cradle of Growth and Urborg, Tomb of Yawgmoth smooth out your color needs while Krosan Verge and Myriad Landscape add some ramp options to the mana base
I think even if you are not playing Lordly Lode or Beryl you can still play Drillbeam at 3 as a board breaker going second, or a powerful interuption going first
Raul, Trouble Shooter Steel Mentor: Raul's yet another companion from New Vegas, a mechanic and former rancher from US occupied Mexico who was Ghoulified by the Nuke that hit Mexico City
Terminus Another board wipe that sees very little play in Commander despite being a competitive house in other formats