hum, a simple thorn carapace with afla would work better for a lockdown, you already have the AMs and flooding...
i had made this deck before singularity, wich slow down the rush, afla was a too slow process for old rainbow starts, maybe now i'd will insert it.
you know, this deck is the complete opposite of a rush, i would say you dont need Snovas in there at all, a bit more quantum pillars will do fine. Changing the mark to
so you can get those hourglasses out faster (only one is not enough btw) and focus more on your lockdown strategy, so you dont need that huge amount of shields. just my 2