I think it really depends on how useful the actions are, since every turn earlier you pick up Uni is an extra action and time to use every other action, if you're just grabbing villages/cantrips with uni, then well, don't pick it up, but if you're getting good cards I'm pretty sure you want to open Uni and then switch to pool since extra plays outweigh slightly faster early cycling. Anyway, when your deck is 11 blanks and 1 SP, the Pool is pretty useless, so I might even advide opening IW/Something over Potion/Something in an SP game,but I'm not sure if I'm right.