Depends on the price really. 94 S isn't going to come back as many times as 85 CC, so if the 94 S is at a good price, go for that one and maybe wait for a similar deal on the 85
Ultimately go with the one you like the most. You also have to look at the availability of each coin. If one of them seems much more difficult to find in the condition you want, go with that. I was in a similar situation last night, I slept on it and bought a new coin today. I was deciding between an 1879 PR 62 Trade Dollar and a Liberty Head Double Eagle in MS-63. I went with the Trade Dollar. I'm doing a TD type set for one thing and the 1879 TD is much more difficult to find. The Double Eagles are being sold by the dozens, so I'll just wait for that one Good luck with your future new coin.
I assume you're talking about Morgan dollars and not $20 Libs. I'd have to see both coins. If either is ratty for the grade or I don't like it, pass. On paper, assuming both are textbook for the grade, it looks like the 85-CC in 66 is a better buy. Price jumps big in 67 and population tanks. For 94-S in 62, there's a significant population in 63 and higher, and the price of a 63 is not much more than that of a 62.
I found those coins last night after reading your first post. (Where's the Buy It Now button) I would buy the 1885 CC between those 2.
I think I'd just pass. The 94-S because it's not a good value (see earlier comment), and the 85-CC doesn't look like a solid 66. If I said the 85-CC was graded 65, would you be thinking, "this is going to upgrade?" Take a look at a lot of images of other coins in those grades and see where these fall.
