Another thing I really miss AND AWAIT (hint, hint) is Ask Cortana about ____. It's nice because it pops out a panel w/out & instead of leaving the page being viewed. Sometimes it's not necessary for an actual full 'seach the web' NEW page AND can't see where you were, anymore. This is not cool!
Also, really, miss Reading view & a slew of other familiar things. Trying to be patient and tell myself the stuff, actually, WILL be there soon. Better be true!
One major thing that is wrong to change is panels for 'enquiries'* that do not take one from the page or site being viewed.; does not go to its own new tab. Including, the Ask Cortana panel... of course, Ask Cortana is missing competely. At least, don't see Ask Siri. Often the Cortana panel is enough info instead or before a full Bing search page.