The Twins seem to be made to work in the Foundry. Early game, they create a one ice scoring server behind Eli 1.0, making it impossible to break it through clicks alone. Twins behind Cortex Lock creates a 4 credit OHKO against reckless facechecks (especially potent for the usually safe 1st click runs that people usually do against HB). Behind Architect can potentially save you 4 clicks worth of installing (let's face it - it's rare that Runners will run twice on Architect without something to break it). Late game, Twins can force a double run on Ichi 1.0, and also allows Agenda bait, pretending to be an Ash and potentially wasting Runner clicks and money getting into check.
My main problem with this deck always was closing out the game; Frequently ending on 5 or 6 points, unable to throw down an agenda safely on the opponent who had, by then, figured out he needed to money-up. So throwing in a Biotic Labour and SanSan seemed necessary.
Cortex Lock for Tollbooth. If taxing becomes more important, but this bigger issue is the codegateyness of Tollbooth. It really skews the deck against Gordian Blade. Fits better with the Next suite I think.
Private Contracts for some other asset economy. Although PC rarely gets trashed by the time i've clicked off it twice, I feel like I could do better. Eve I think is too risky given the dedication of ETR ice to a scoring server/plugging leaks, though.
Whizzard gives me nightmares... Being able to trash most of my stuff for free is just too good to combat, and you can bet he will be checking every server created. The best bet is to get him to run servers so you can draw out your ETR ice and try to create a scoring server, but this doesn't help against Net Ready Yogs/Mimics... So yeah, if you have this in your meta, good luck. Perhaps more Operation Economy?