You need to consider how you wish to proceed if you want the rewards from GE (especially the final level) while designing your city. If your boosts and troop selections aren't sufficient then you'll need to do some manual battles to help get you through some of the harder level 4 battles. If you don't find the prizes worth it then don't do the battles. Many people find the prizes worthwhile. I suspect at least part of the problem you have is comparing apples to oranges. GE gets much easier when you've built a city to go as far as you can in GBG (which also gives better prizes on average). Just like the daily quests. If you don't find the prize to be worth it then skip it. Same for a lot of the aspects of the game.