Playing Parasite recursion and Suckers in Nasir makes standard RP much easier, I find. You can insta-kill Komainu and Tsurugi on rez, for a profit. I also run 1x Test Run, which is nice for unexpectedly Femme-ing into their remote. Obviously it’s still a hard matchup but with a bit of tech for it I don’t think it’s much harder for a well-piloted Nasir than for any other Shaper.
I agree with Clamatius that tagstorm is a horrible matchup. Toolbox helps, kinda, with the 2 link, but since Nasir is generally so poor it’s real hard to beat traces when you need to. A good trick if you do get tagged though is to put out more than one Workshop and spread your stuff out over them. At the very least it doubles the click+cred cost for the corp of trashing them. Never put more than one thing on a Shop at a time though.
On-topic, I find Blue Sun is a real mixed bag, as people have been saying. D4v1d is a necessity in Nasir because of that matchup I think. Again, Parasite helps a lot for Ice Walls. Occasionally the BS player will think they can get away with giving you a bunch of money off a rez and still keep you out, and again this is where Test Run is good as it provides a quick unexpected answer to whatever they rezzed, funded by the money they gave you. I’ve not played Nasir against Bootcamp BS yet though, I imagine that’s a different kettle of fish.