This is a rare occasion I disagree with glennsfc. I would run it all left to right. In either the living room or hall it will carry your eye into the room and make each look wider. It will make the family room look deeper. Running it all the same way will aid a look of continuity even though the three areas are separated by the foyer. When there's a debate about floor direction I encourage the customer to lay out a box of material in the doorways in either direction to gauge the look.

There are several things that must be considered. I like to use the concept of MOST amount of flooring that follows the general rule. If you have a single room (lets say 10' x 10' = 100sf) and then the REST of the space is much, much larger (say 600sf), you would want to try to keep the MAJORITY of the flooring (600sf) sticking to the rule of "longest length = long run of the room". The other question with hardwood becomes wooden subfloors. Sigh. Wooden subfloors over joists change the equation. Hardwood floors must be run perpendicular to the joists - no matter how big/small the rooms are. So...without knowing your set-up, without knowing your subfloor, without knowing the direction of sunlight, without knowing very much of anything about your situation...the majority of the home should follow the rule of thumb. Unless other factors contribute to changing this. Which I can't tell because there isn't enough information. And just for fun...diagonal is always an option = 15% waste and a more expensive labour bill.

Vinyl products do NOT like anything soft/squishy underneath them. In fact they can separate or break their own edges if you have underpadding underneath. If the Pergo vinyl has an attached underlayment, then it is DEFINITELY NOT allowed to add anything else. This is NORMAL for vinyl. In fact it is a major drawback for all vinyl products. Underpadding is not allowed with 99.9% of vinyl floating/glue down/perimeter glue products. The installation instructions will tell you what is ALLOWED to be used. If it is listed then it is allowed. If you do NOT see it listed, then it is NOT allowed. It is an easy rule to follow. Continue with the rigid underlayment (like you did in the bathroom). The noise reduction from the attached underlayment is the only padding/accustic insulation you are going to get.

At this point, the job ($4/sf for a BIG job with LOTS of things to do = awesome price) is finished. The cure is going to be worse than the disease. I'm a big fan of "Wait until you have a problem before throwing money/time at it." It is the cheapest solution I know of (I'm a pragmatist...who is both cheap AND lazy ;-P). My advice is this: leave it alone. Keep 10% 'extra' of the flooring product (roughly 75sf or to the nearest box). This will offer you the peace of mind and the material security you will need to feel secure. You will keep it in the back of your mind. You will know that IF something goes wrong you have ALL THE PRODUCT needed to repair/replace the damaged planks. With a laminate floor I wouldn't worry to much about a bit of bounce. People have 'put up with' bouncing laminate floors for 20 years (the SAME laminate they installed 20 years prior). That tells me the click system is fine. Your floor is a rigid vinyl (8mm thick = nice product). The rigidity of the core will help keep everything stable. The only weak point (as in everything in life) is the link (click edge) between one plank and another. This is the one and only place things *might go wrong. Now to be blunt, a rigid vinyl floor like yours can be taken apart and, "in theory", be clicked back together - BUT I don't like that idea. I really don't. We know the click-edge is delicate. We know that. We've seen them brake by grazing the ground before being installed. A vinyl floor that has been disassembled has a STRONG likelihood of DAMAGED edges. If the edge is damaged then there is almost no way you will get them back together. That means you will have to assume 25% damage should you choose to 'unzip' this floor to the point where it bounces. That leaves you with 75% intact flooring with 25% garbage planks (which must be replaced). As soon as you try to fix the subfloor underneath (by removing the flooring) you will have lost the 'intact' floor. You are guaranteed to spend MORE time, MORE money and MORE materials to deal with this. Compare that to 'leave it alone'. Right now you have 100% intact flooring. Every day you wake up to 100% intact floor is another day with a perfectly functional floor. Every day you have 100% intact floor is another day you have SAVED time, money and materials. Simply leave this floor alone until something MAKES you repair it. Keep your 5%-10% extra on hand for future repairs (and there will be future repairs). Use them if and when you need them.