Two firsts for a guy who is essentially a half year rental? No way! If we were talking about a true difference making guy who deserves a max deal so his bird rights would matter, then yeah. Howard isn't that guy anymore. He brings some strengths, but also comes with liabilities.
I'd do one first, Amir, and a second with Jerebko and that's about it.
Amir is worth much more to us than the 24th pick in the draft. We have too many picks. We already have too much mid-late 1st talent at the end of the roster. Two non-Nets 1sts is worth the chance to make the Finals.
To me, Amir is less important if we bring in Howard, considering Amir's most prominent role for us right now is the rim protector. That said, let's say Sully is included in the deal, then I'd probably like to use Lee as the salary filler and keep Amir. Amir does a lot of little things well.
Basically, if your using Amir as the big salary piece, you take one of the picks off the table. Amir is a much more valuable player than David Lee. Even though both probably would help a post-Dwight rockets team, you almost have to give them something like the Minny pick just as value for taking Lee. Then probably a guy like Sully or Zeller and another 1st for Howard.