Um... probability of decking out with no eternity is 1 in 35... so that means about 3% of your games should be lost because of this.. not getting a shield in 15 games, where there are 4 shields in 35 cards (+ miracle) and it's a speed deck is also VERY unlikely
... I wouldn't add a second eternity (nor do I have one) since it's an extra card and not having it only screws you 3% of the games...
A few notes, again, don't try to fight rainbow and divine glory.. just quit.. it's going to be a loss anyways... for the remaining gods, I stand by my 70% estimate, I won like 29 out of 43 games I last played which is 67%... and frankly a few of them were accidental losses (ie, i decked myself out with an hourglass once, I forgot to use eternity twice, I didn't draw eternity 'till the very end once). ... if you don't count them then it's 29 of 39 which is 74%... again, just quitting on rainbow and divine (and not counting them)...
Try to play shields in order bonewall -> phase shield -> phase shield -> bone wall... Don't play miracle till you are about to die... I mean.. there IS a learning curve with this deck...