I am not a student of suspension. I have browsed it to at least know what I don't know, and to try and understand what most are talking about. But, I see a ton of things in Video. Especially slow motion. It is then important to talk to the drivers, and show the video to get their feel. It seems every suspension is a compromise even WITHIN an intended environment of use. It seems there are so many interactions that the scholars come up with, which may be ignored, that 95% of the time they miss the sweet spot. Video will show all of them, including tire movement which may lead you to an even greater camber curve than anticipated.
It would be interesting if the FSAE program includes looking at video from past builds. From that "information," the "ideal" camber curve (to the ground) would generally drop out. Then, it is deciding what is important in the straight line and turning. With IFS/IRS, camber to the ground seems most effected by body roll and the single tire hits. It goes on, but I think, the point I am trying to make is: Think about what you want the tire to do before you even think about suspension geometry. Rear suspension is relatively easy as generally 3D. But it gets real challenging when adding the turning equation ...and the camber/caster gain curve associated with that.
When I had a current build IFS "engineered," it required simulation and not normal CAD. I specified exactly the camber curve at straight and turning(39*.) It was then up to him to work the geometry, and then compromise on camber/caster where it hurt the least. Where it hurts the least in our environment (offroad racing) seems to be straight and at ride height. A few degrees of negative camber at ride height is not noticeable but helps when the suspension is at the extremes of both movement and forces.
We have a saying that, in rough offroad racing, the race is won in the rocks and tight turns but lost in the open straights. Suspension geometry allows precise direction and turning, while shock tuning and HP allows speed. Really loosing is crashing at speed or bicycling in a turn.
From video, we can see differences in body lean and effects on suspension. Interestingly, we study IFS camber curves with body parallel to ground and at 10* body roll (from roll center) and max turning (36-39*). In the rear, we only look at camber curves to 5* body roll as front jacking usually picks up the tire under speed. At low speed, body roll can go to 20-30* but the slip forces are not there...And offroad tires usually carry the tread into the sidewall significantly. (As a FYI, you can carry the tread too far into the sidewall to where it affects aero. We have seen 75hp "saved/lost" in changing sidewall tread profile on a single roller dyno.)
There are more knowledgeable contributors who will chime in. I listen for more of their thinking than to their "numbers" as each car has a different purpose.
Always learning. Others have been here before. Rocket science only works in well controlled conditions.
