OP, You are going to be there in the broiling heat of August, so I think the thing you'd miss the most is
Genie+, since standing in outdoor lines will be excruciatingly difficult unless you love standing on a hot pavement with very little shade in 95+-degree direct sunlight.
Even with rope-dropping, you can't hit all the main attractions in the half hour of ETPE. It's just physically impossible. Since you've never been to WDW before, it's hard to imagine the sheer size of each park. It's quite a walk from, say, Soarin' to Frozen Ever After. To get them both in at RD you'd have to (a) get very lucky and (b) sprint. Even then, you'd probably end up waiting 45+ minutes for one of them.
As far as mobile ordering is concerned, you don't have to mobile order everything, but there are some QS restaurants that you'd be pretty unhappy to stand in line waiting for your food. Woody's Lunchbox is the one that comes to mind immediately. So don't think of mobile ordering as an all-or-nothing proposition.
If you do decide to get G+, you are going to need your phone. I was wondering from your first choice if perhaps you don't want to carry a phone with you, but a phone is handy even without using mobile ordering or G+ since you can look at your phone and see wait times--invaluable info.
A MB is unnecessary but convenient and since there are 5 of you, it'll take you longer to tap in to the parks, to your LLs (assuming you'd get G+), etc., since you'd have to get out your cards, etc., etc., With the MB, you'd all just have it on your wrists. But plenty of people don't use MBs anymore, especially since the new ones (and the old ones are apparently not available anymore) are so expensive.