I run 4-5 cores on all longbows. I say this because the veneers are part of the core. The core is everything between the glass. 2 veneers, 2 tapered lams and sometimes an additional parallel.
I’m sure your plans you refer too mean 5 cores, including any veneers. Surely you wouldn’t have 2 veneers and 5 additional core lams
BTW I have noticed no difference between a bow with few thicker lams and a bow with more thinner ones. All else being equal. Nowadays I use more thinner ones as I feel it is more durable.