Cover is first, core strength effects if the ball slows down properly...surface is 75%
so what about the layout then? or is that part of the core?
Yes.
As far as I understand static weights in today's environment ---
As has been implied, thumb, top, bottom and side weights are no longer applicable in helping to determine how the drilling will affect the roll and other traits of the vast majority of today's dynamic cored balls.
They are/were significant for what is termed pancake cored balls int he 70s/80s and part of the 90s. Today, maybe 1 in 10,000 sold balls
used for strikes have a pancake core; most polyester and many urethane balls still use pancake cores, but again the majority do not use dynamic cores (obviously some do).
Most people only consider static weights to insure a ball is technically legal AND to leave room for a potential weight hole to affect the flare and the dynamics of the drilled ball.