Just my 2 cents - I have default setting of aligned/back and 8% seam gap from my testing and found this is pretty much the optimal for my prints that I re-saved all the profiles with it to never change it again.
edit: it obviously depends on model, slice what you are doing sure! But at times it is also helpful to know what “just works” 
The above advice Olias gave is a great start to figuring this out…