TL;DR - If you already have Ultimate Collection, just play that. Anyone that hasn't play The Sims 2 (or at least got an copy), I would advice to just wait for EA to update the game to have less crashes and bugs.

As a Sims 2 veteran, I wish I can say "Yes, this is worth having" but Legacy Collection is buggier compare to Ultimate Collection. EA has said that they are working on fixing the bugs and asked to report it to EA Help's Forum which I hope they keep to their words and so do as it felt rushed and not properly play-tested.

IKEA Home Stuff Pack isn't included but there is a guide to install it for Legacy Collection. I would recommend it if you are going to download custom neighbourhoods or lots as before Legacy Collection, we used Ultimate Collection which has that stuff pack.
https://steamproxy.net/sharedfiles/filedetails/?id=3418201905