Surges of power should be made more frequent, because:
1) They balance the loss of random artifacts due to stomafillia sacrifice nerfing and possible casino gold nerfing in the future
2) They're fun
3) They add randomness and replayability to the game

Additional idea: I don't know what's the specific plan for the crowdfunding reward monsters, but they could be good canditates for surge of power artifact guardians. And if surges of power were more frequent, we would see our monsters also more often.