I can already see it, this deck is going to be janky and degenerate...I like it. Add some blue spells that counter and that also cause a loss of cards off the opponent's library and you should be good. Also having other creatures that mill as well such as
shriekgeist and
mindshrieker would work wonders for you. Also if you Try to stick to the Dimir Guild as much as possible you may see some satisfying results using creatures such as
balustrade spy,
deathcult rogue, and even
undercity informer will work wonders for you.