I think a couple of Crypt Incursions could add some great stall potential to a mill deck, but no need to test that right away.  For now, I might suggest you just drop a couple Deprive to get down to 60.  You only have 2 landfall cards in the deck anyway.  You might find later with your card draw, that you only need 20 land in this deck.  Then you could put the Deprives back in.

Well, you are trying to stall the game while you mill.  And this deck probably won't work too well in multiplayer except that people might pity you while you charge up mind grind with all of your card draw.  Assuming a 1v1, you're just trying to buy time while you mill.  So it's not worth including a creature/spell that doesn't do one of those things.  While 10 creatures sounds low, you do have a lot of card draw to help you get some of those fog banks/gomazoas out.  I'm not very experienced with low-creature decks, but I think 10 is a good start for testing.  If you were going to add any more, then I would ideally want them to be guard gomazoas/hedron crabs/mindeye drakes.  Speaking of stalling/milling, mindeye drake is kind of a bomb there but it is infortunately a tad pricey.

Hmm, I'm sitting at 62 cards right now (see above). Suggestions for what to drop?

How many creatures do you think is enough for this kind of deck? I'm thinking 10 is too few...

5.  Deprive might be a good counterspell for this deck as it combos with Hedron Crab's landfall.

4.  I prefer See Beyond to Divination, but I don't think I've ever tried Think Twice.

3.  As you get better cards for this deck, I would recommend considering these for removal:  3x Kraken Hatchling, Wall of Frost (no flying or reach), Vedalken Entrancer (too slow), Far // Away & Silent Departure (bounce spells distract from theme and don't combo with anything), Chronic Flooding x2 (you'll hate drawing this later in a game), Curse of the Bloody Tome x2 (too slow), Stormtide Leviathan (might be a good stall card, but too pricey to not be milling or drawing cards)

2.  Looking at your casting costs, I would probably split the lands more evenly between island and swamp.  Maybe try removing the reliquary tower and doing 12 island and 10 swamp.  You can tinker with the ratio later as you get a feel for it, but I'm betting you won't miss the reliquary tower.

1.  Vedalken Infuser and Grindclock is fairly tenuous.  It's a rare combo in a deck of 60 cards and one will be mostly useless without the other, because they don't fit the deck theme.  Grindclock is generally too slow to be good without the infuser.