If you want 7.1.4 you put your rear surrounds at 120 and put your side surrounds at around 70 degrees (+/- 15). This will give you a much better effect than just surrounds at 120, IMO. You could still then add front wides at around 45-50 degrees.
Or yes, you could do 5.1.4 + front wides and have them at the conventional angles (~50-55 for front wides and 110-120 for surrounds. Many complain, however, that a lot of Atmos soundtracks don't use front wides much, if at all. However, most AVR/AVPs copy side surrounds to the front wides if you do 5.1.4 + FW.
What this means is that in essence, you have an array with front wides + side surrounds playing from the front wides and side surrounds + the folded rear content playing from the side surrounds (i.e. sides play from two sets of speakers which is an array and will image in-between instead making side surround sounds come from a "phantom speaker" in-between the front wides and 'side' surrounds. This means sounds for front wides will play from them, sounds for rear surrounds will play from the side surrounds and sounds for side surrounds will play from a point between the front wides and the side surrounds. Notice this images pretty much the same as 7.1.4 in option 1 except there the front wide sounds phantom image instead of the side surrounds.
Atmos, however can use something called "snap to" if the mixing engineer decides to use it, which means the front wides or other speakers might not phantom image because the sounds will be moved to the nearest physical speaker instead. I don't know how common it's used since you are generally unaware it's there without a way to compare. DTS:X doesn't use anything like that by comparison). Otherwise, effectively both options will sound very similar in actual practice for that "copy" reason and why the other guy's advice has no useful meaning whatsoever as it's clear he has no idea what the AVR/AVP does with 5.1.4 + FW. I'm doing 11.1.6 here, BTW.
If you want to do 9.1.6 in the future, I suggest you do the 7.1.4 option and add front wides later. Of course, unless you're going to hard mount the speakers, they could always be rearranged instead.