"Groudon Dilemma - How to optimize usage"

#PokemonGO: I love Groudon and it is one of my favorite Pokémon. Between Heatran raids and recently discovering how Mud Shot/Earthquake is pretty useful in PvP, I want to use it more. Of the following options, which would you recommend and why:ResourcesSpend Rare CandyWait for Groudon to return to raid battles and farm themSpendingUnlock 2nd Charge Move (Solar Beam/Fire Blast)Power upI can provide specifics in my circumstances but am more wondering for the general case. Thanks in advance.EDIT: Thank you to everyone for such thoughtful, complete responses. I really appreciate this. via /r/TheSilphRoad http://bit.ly/2Ru7I8B