Are you able to give details on the online infrastructure? Virtual console as well?
Online connectivity outside Wifi isn't coming until a patch "prior to launch" according to Nintendo. No eShop, no online, no Nintendo Account linking in our current review units.
Bright side: the Wifi with sign-in page issue? (The Switch currently can only sign into open or password-protected wifi because it has no web browser.) Nintendo confirmed the patch will have a fix for that.
"Ability to connect online using hotspots that require authentication, such as at a hotel or café. A web applet will open up so the user can sign-in or accept terms of use."
Do you also feel that the sticks and buttons being directly on top of each other makes using the joycon grip feel awkward?
The most awkward this is the shoulder buttons for me. On the Joy-Cons they're a bit too small for dual fingered use. Index fingers only, unless you're on the Pro controller.
Are you also having connectivity issue on the left joycons?
Nope.
It's under User Icon > Add Friends, but it currently doesn't work.
How speedy and efficient does the UI feel as a whole?
It's pretty quick. Capture button use is snappy as hell for example. Returning from Sleep Mode too.