If the draft ended right now I'd say those would be the two guiding principles of the Jets defense.
We tend to get too caught up in 3-4 versus 4-3 schemes. There are very few true 3-4 defenses (the Steelers, maybe) that two-gap all their DL etc. Most of what we call 3-4s (the Ravens, for instance) are 4-3 "overs" or "unders" where one of the DEs happens to stand up. See this excellent Cossell article for more:
Rex's approach has always been multiple fronts, so I'm not really worried about Richardson in terms of scheme fit.
But I do think the pick, along with the rest of the Jets defensive personnel, suggests the two things in my title.
1) The pass rush is going to come mainly from the front four. Pace and Barnes will likely be joined by a mid-round pick, but the 2013 Jets aren't going to have an elite pass-rushing OLB, and that's fine. Why? Because the 5-man DL rotation is Coples, Ellis, Garay, Wilkerson, Richardson, and four of those guys are capable of being very good interior pass-rushers.
2) But, it's still the case that you can't have a DL that big (Coples is the "speed" rush end in this scenario, which is kind of amazing) and not have to make up for it against the pass elsewhere. This is why I think the Jets will be in nickel and sub packages more often than they'll be in any "base" package. Harris and Davis are the two most versatile linebackers on the roster, and I think you will see them play close to 100 percent of downs. Sometimes they will be supported by Pace and/or Barnes, but more often I will bet they will be supported by a mix of 5 dbacks. Worst-case scenario seems to be Wilson outplaying Milliner in on the outside, and Milliner playing his rookie season at nickel. That's still a lot of talent at corner. Likewise, you mix Landry, Allen, Bush, and a draft pick at safety, depending on whether you want to lean run (Allen) or pass (Bush).
Picture a 3rd and 5 against the Pats in a big spot. Coples, Richardson, Wilkerson, Barnes, Harris, Davis, Cro, Milliner, Wilson, Landry, and Allen line up against Brady in a 3-3-5, showing amoeba blitz.