I, too upgraded from the 6s+ to 7+ @256GB (matte black, not jet) and I'm definitely not regretting the upgrade but quite the opposite. The increase in storage space, camera, speakers. Even the A10 as it's definitely noticeable playing games like Real Racing 3 and other recent releases with incredible graphics and different nuances (muffler smoke puffing at the start line) as well, NO drops in frame rates from 60fps. Even small drops I notice on my 9.7" iPad Pro aren't there on my 7+/A10. The extra memory continues to keep pages open in Safari allowing filling forms out while researching different elements for said form on other sites
Many say the looks are identical, something I've found not true, from the new black colors to the way the camera bump's been molded into the hardware ...as well as the Apple phone cases using real metal for the buttons in the leather tself, LOTSA cool, small, you'll keep finding while continuing using 'Easter Eggs' for lack of a better term and that killer camera ....with massive storage tanks to ingest the 4K footage!
Love it and can't imagine going back so my advice would be to keep the 7 wrapped up if you're serious about keeping (& enjoying without wondering) the 6!
GL
J