This app was mentioned in 15 comments, with an average of 2.00 upvotes
KXNT's pop UI icon is perfection
Hands down one of the best material/flat/simplistic icon packs out there.
I made my own knockoff of iOS using Pop UI, Nova and Kustom.
Icon theme:
https://play.google.com/store/apps/details?id=com.launchertheme.kxnt.pop&hl=en
Wallpaper:
'Great' from the Samsung Themes store.
And if you're prepared to deviate a little further from iOS design, POP UI is by kxnt so it has quite a few icons
Pop UI is really good too.
I really like Pop UI.
That is also from Pop UI
I came from iOS to this phone, and I too used to do a lot of jailbreaking. I'm probably just echoing stuff other people have said here, but here's the things you should do imo:
Now for some advice. Recovering a bricked or semi-bricked Android phone is harder than recovering an iPhone imo. You can't just put it into DFU mode and plug in iTunes, and restore. So make sure to be cautious. Most of the time you can still boot into recovery on Android though, so if you're the experimenting type it should be fine if you're careful.
I would really suggest waiting for CM12s, and not flashing OxygenOS. I've heard bad things about the battery life, and if you jailbroke for themes and such, CyanogenMod is much better for theming. Also, if you like theming a lot, look into using a different launcher like Apex or Nova (I prefer Apex, but 99% of everyone else prefers Nova). If you want to keep a similar iOS feel, I suggest the Pop UI icon pack. It isn't free, but it's worth the money imo. It has a ton of icons. Also, if you prefer iOS emoji, install this after you root.
Feel free to ask me any more questions. The last thing I'll leave you with is this: http://inthiaano.com/oneplus-one-toolbox/. It's a toolbox thing that basically automates unlocking the boot uploader, flashing a recovery, etc. Very useful tool, especially when starting out.
Horuzon is actually a rip off of Pop UI :/ pop ui has way more icons https://play.google.com/store/apps/details?id=com.launchertheme.kxnt.pop&hl=en