To give you some actual answers to help..
First, for those who either live in the area or have experienced that time of year- How is/was the pressure?
It can be very busy, to quiet. Its very dependent on the year, the week you're there and where you're fishing. It's typically quieter then the fall, however if stuff blows out you'll get stuck fishing some stuff that may have more people around. There is less water to move people around to, as well.
Second, I assume (according to maps) wade access is fairly limited so I'm debating packing my watermaster. Are some of the lower Skeena tribs easy to float? For example, studying maps it looks as though 10-13km above the Kitsumkalum/Skeena confluence there are some decent rapids? I've heard of large logjams on the Kitimat as well. Any areas to avoid due to water hazards?
Wade access can be limited, but you can walk in most places for some good runs.
You do not want to float the kalum in the canyon. It's not a rapid, its a canyon. There are two distinct portions of the Kalum upstream and downstream of it. You can only float the section upstream if you get access across private land to pull your boat out (not gonna happen).
For other access, go talk to Fish Tales in town, and make sure you ask for any logjams on the Kalum or Kitimat. There was a mean one on the kitimat the last few years that you cant see from the launch that was swamping boats.
Lastly, and this might be best answered by locals but how has the winter-run been so far and/or spring-run predictions? 2019 looked to be rough for the entire year in the area. Also, is it true the Terrace/Kitimat basin's are experiencing a lower snowpack than normal (it's low up in Haines which could cancel my plans), but I'm more curious for spring runoff potential.
Too early to tell what the run is, but based on last fall, probably not great. Pretty much the trick with skeena is just going and hoping for good conditions. Can be the best run on record but if the water conditions are crap, the fishing will be marginal.
You can find snowpack info with some googling. Skeena/Nass is at 93% of normal..so pretty average snowpack year