Well, these are my personal guidelines. Also, I don't seem to have a reaction to CA, so there's no physical reason to avoid. For this build, I used a fair amount of CA. There have been builds I've done in the past where I used very little CA and almost exclusively used AR. Although their usage properties are very different (one bonds almost immediately, the other cures after some time), I consider them generally interchangable in terms of their function. AR is more forgiving and sands extremely well. If you find you need some additional working time with an assembly then AR might be the way to go. I sometimes use it when attaching the leading edge sheeting so I can work the sheeting and deal with any challenges that pop up. Also, the sanding in this area is made nicer if you use AR. Obviously, there are times when you need that instant bond, so CA is the only option there.

CA's advantage is obviously speed. IF you frame up an assembly and have it square/aligned/straight, etc. hitting it with CA is extremely fast and efficient. The key is to use only enough to do the job. If you have well aligned parts, you can use thin CA and let it wick into the joint. When you're able to do this, there no mess and little sanding frustration. It means you've cut/sanded pieces to fit exact - even kit cut pieces may need some work here. If you use CA and the parts are not alligned or there are gaps you try and fill with med or thick CA, you will have sanding issues later on (sounds like you've been there).

Regardless of adhesive, there is no substitute for quality woodworking skills.

I use Epoxy for all high stress joints on a build. These would be Firewall, Wing Joints, Tail Feather attachments, Langing Gear Blocks, etc. I also use Epoxy to fuel proof.

As for hard woods, it would depend on how they were being used in the build. High stress area = Epoxy. AR needs a porus surface to properly bond, your hardwood might not have taken to the AR like you were hoping.

For an exhaustive dive into adhesives Airfield Models has a great page [link=http://www.airfieldmodels.com/information_source/construction_materials_for_model_building/adhesives.htm]here[/link].

-MA