WilDV, I'm not trying to sound like a d**k here. Really not. You said in another post you're a young engineer - we've all been there and understand there's a learning curve in translating our education into real world experience. That said:
1. This calc should not take more than a page or two, including accounting for 2nd order effects and slenderness. 60 pages is alarming. Quantity does not equal quality.
2. After 60 pages, you should know what the dimensions and properties of your stiffening elements are, since that is the most critical feature of this design as you've laid it out, and as noted above.
3. "hurricane level 2" is not language found in ASCE 7 wind load criteria. Unless this is in Florida and is something addressed in their state code (which I'm not familiar with), not sure how you translate that into load on the structure, and it therefore has no meaning in this context.
4. "Doesn't the provision/local building codes consider most of the order effects? I thought that was why we use provisions." Not quite sure what you mean. Assuming you're designing to IBC & the applicable state building code (all of which reference IBC, many with amendments), IBC adopts AISC 360 by reference, and this problem would clearly be subject to AISC 360 Chapter C requirements (stability and 2nd order effects) in addition to the Chapter E requirements. More plainly, when your canopy sees net uplift, the rods will no longer be "taught" and will therefore have a sag to them due to their self-weight. The sag will cause your compression load to become eccentric, creating a bending moment in the rods which will cause further "sag", causing further eccentricity, larger moments, more sag, etc. If this 2nd order effect does not converge to a steady state, your rods are unstable for compressive loads and therefore have no compression capacity. Note this is a separate issue from pure buckling, which is covered by the Euler equations in Chapter E and nominally accounts only for P-"little delta" effects (the sag eccentricity issue is a P-"big delta" effect). The alternative to all of this is to treat the rods as tension-only and, as kevo noted, design the canopy as a cantilever for the uplift case, or to make the canopy heavy enough that there is no net uplift.
5. Just because you've seen something "designed" one way, doesn't mean it's correct. I deal with a lot of old existing structures, and everyday we see things that we would never design as new construction, whether it be just because of more stringent current code requirements or because the old design was more generally inadequate or even incompetent. Unfortunately this is too often also the case on new stuff we see from other vendors, too (first time you see someone spec A325 anchor rods, or give you loads from their structure in a high seismic zone that don't include seismic loads, you'll know what I mean!). I'd guess most canopies we see that only have slender rods either have no net uplift, have been designed for cantilever action under net uplift, or have been significantly stiffened as Phalanx mentioned.
I just hope you're being truly overseen on this by competent licensed structural engineer(s). If not, get in their grill with lots of engineering questions and force them to pay attention to what you're doing, and run away from that place fast if they don't.
