I haven't seen this topic before. I love this game and want to sleeve the cards, but it's already a tight fit and I'm not sure they'll fit back in.
They don't, unfortunately.
Which is a bummer as I like the inlay too much to remove it. So I ended up putting the base game and all expansions I'm currently using in a different box.
Additionally, if you do have it sleeved, which ones are you using?
I always use Ultra-Pro. Sturdy, and after a few shuffles the slipperyness goes away and they stack nicely.