Battlepacks: Should I store them longer and open them all together at once?

You asked multiple questions in one post (which is discouraged), so I'll answer the IMHO most important one:

Should I store Battlepacks longer and open them all together at once?

• There is no bonus whatsoever for opening them later or multiple at once.

• As you already said yourself, you got pretty highlevel stuff very early, so what you get is independent of when you open it.

The only "but" here is:

• There are weapon-specific battlepacks that are unlocked when you reach certain kill counts with that weapon. If they contain attachments, those attachments will belong to that weapon.

So if you open the general battlepacks first, it could theoretically be the case that you get all the attachments for one weapon and then, when you get the weapon-specific battlepacks, there are no attachments for this weapon left to be unlocked, so all you get are Boosts or Dog Tags.

For this specific case, opening all weapon battlepacks first might be better. But after 600 hours of playing Battlefield 4 I can tell you that this will take a long time and it will not really matter when you open those battlepacks.

So I suggest you open them as soon as you have them.