Hello and welcome to the forum!
Well, I would certainly wait a week or so for the Apple announcements, some predictions
HERE - my wife is the main user of our iMac (I'm on 2 laptops over a home network) - her computer is now 3 1/2 years old but still going fine (21.5" monitor - her choice - I'd have pick the 27"; but not a retina screen; 1 TB fusion HD - she does not need that much storage; and 16 GB RAM - had to have added on initial purchase).
Now, I might buy a new one maybe spring of 2017? So, I looked on the Apple website and priced the system shown below - would likely have to stick w/ the 21.5" monitor (but would try to talk her into the larger one) but would get the retina screen; would add the extra RAM for a total of 16 GB; and also change to a 512 GB SSD. You're likely to receive a bunch of advice on this topic, especially picking a high resolution 27" screen. Good luck in your selection! Dave
ADDENDUM: Well 'beat to the punch', as predicted!
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