Sorry to burst the bubble guys - especially those who have blatantly knocked down WP over iOS. None of those posts have mentioned anything real to address OP's usage at all.
Let's say OP has a business that needs employees to be:
Always connected on Exchange email - WP does it.
Always connected to their docs and do realtime sync of docs between SP3 and WP - WP does it.
Always be able to share docs without clogging emails by a central OneDrive storage - WP does that.
Be able to use Lync or Skype for business communication or calls - WP does it. (you can even elevate normal voice call to Skype call!)
Sync Notes and share notes amongst themselves - WP does it.
Be always connected for a short term project and make notes, share photos about products/client sites - Create a Room for quick chats right within SMS hub - WP does it.
Sync Business address book that is updated on all WP as well as SP3 - WP does it.
Get 1TB of storage per employee with Office 365 subscription - SP3 and WP does it!
Guys, I agree, Office is slightly better on iOS than WP but OP clearly mentioned they've moved onto SP3 so they would do major work on SP3 when it comes to Office. What they may need is being able to make quick edits on WP on their Excel or PPT - WP does it!
Cortana - she will remind all employees of their appointments, track their flights, remind them to say "You are amazing, boss!" to their employer every time they reach work.
If the employees are free during lunch, they can even make an alliance and play Age of Empires on their SP3 or WP - they so can't on their iPhones.