I am struggling with the exact same dilemma. My son has a G5 Plus and really likes it as an upgrade from the Samsung J3. We want to upgrade his mothers phone (X2) and the battery in the E4+ is very tempting.
A couple of things I have considered is that while the lower resolution screen and lesser processor in the E4+ should provide much better battery life, I also consider that it is a larger screen and the G5+'s processor should be much more power efficient than that of the E4+'s.
Another thing to consider is OS updates. G5+ should eventually get the Oreo update whereas I believe it has already been posted that the E4+ will remain on Nougat.
For ~$120 difference, it’s a tough call in my camp. (edit: oh, wait…that would only be a $50 difference for the 32GB/2G RAM, still tough, but easier to justify. )