Yup, same here (if) I was interested in getting one.
Now the 5.5 will have a faster CPU and 0.8 bigger display, but I don't think it will be enough to balance it out vs the 4.7. Apple wants to enter the phablet market in a big splash. They are almost forcing our hand to choose the superior iPhone 6 model with a better cam and 128GB option. Ideally, 4.7 is the sweet spot for one-handed use. But is it worth risking for a near 40% larger battery and potential 3-5 hrs worth more of screen time usage? There are very "little" (no pun intended) advantages the 4.7 model has over 5.5 except better one-handed use. I know because I prefer my larger Mi 3 over the HTC One with a 4.7 inch screen. I hate getting paranoid and monitoring the battery closely more than carrying a larger phone. I just hope Apple can keep the dimensions more like LG G3 than OnePlus One.
Yesterday, a guy sitting next to me was carrying the Asus Zenfone 6. It cost about $240 here but I didn't realize the battery capacity is 3200 mAh vs the Zenfone 5's 2100 mAh. Once you go over 3000 mAh with a 5.5 inch screen or lower, it is very hard to go back to a smaller device with the smaller battery. We get near double battery stamina. I got 8 hrs screen time on my Mi 3's 3050 mAh yesterday mostly Wi-Fi, browsing, music, a few calls, texts, and downloading videos. It could've reached 9-10 hrs if I wasn't downloading videos so much. My HTC One would've been dead by mid-afternoon. Only the single-core iPhone 4 on iOS4 ever gave me 10+ screen time usage consistently. Very few portable gadgets whether from PSP, PS Vita, smartphones, laptops, portable media players, etc ever reach 10+ screen time usage except Haswell-powered laptops or tablets like iPads. And since the iPhone 6 (phab) is closest to a tablet-like battery, it becomes a no-brainer for endurance.
I estimate the iPhone 6 (phab) screen time usage could range from 8-12 hrs vs the iPhone 6 (mini) at 6-8 hrs. Bigger difference than S4 vs Note 3.For me, it is about going for the best model over the most convenient in one-hand or pocket.