I know a lot of people might disagree but I hate skeletal scrying and think it is not a good enough draw card. Unlike time walk and ancestral it has no synergy with yagmoths will. They just don't work for me and since Void is a control deck the time walk and ancestral fit nicely. They give you cards for cheap and more time. Even under void they are still playable but skeletal isn't really.
The problem with the deck that you have presented is that you're significantly weakening the mana-base to play two blue cards (only one of which generates any card advantage), and none in the sideboard. This opens you up to more Wastelands, Blood Moon, Back to Basics, Price of Progress, Dust Bowl, etc. Anybody will admit that Ancestral Recall is much better than Skeletal Scrying, but in the deck I would
much rather play Skeletal Scrying than Time Walk. I was the one who originally suggested Skeletal Scrying to everbody in my
primer here, and it really fits in the deck, because if you're playing the deck correctly, it's essentially a
tempo deck, and Scrying is a good tempo card in here. In most cases you are casting on the 3rd to 5th turns to cycle for a few cards at opponent's end step, and even later in the game it turns into a huge bomb when you can draw 5-7 cards if you and your opponent are both topdecking. In summation, fracturing the mana base for essentially Ancestral Recally is not worth it in my opinion.