Portfolio is very promising. You can use your own domain if you have one, and password protect certain collections. While you don't get as much control as with other solutions, you may not want that, and the integration with synced LR collections is very handy.
One important point to note about Portfolio, is that its usage of a cloud synced LR Collection is not AFAICT self-updating.
I found that ongoing change in this synced Collection will only get reflected into the Portfolio gallery if/when you go in and actively instruct it to refresh and rebuild. This cannot be invoked from the LR end.
Not necessarily a problem, just an expectation to be aware of.
That's correct, and this can be both good and bad. A lot of people will see it as keeping control over adding new photos or changes, while many want things to happen automatically. The synced LR collection is updated automatically, of course, and it's just one or two clicks to refresh the integration in Portfolio.