Usually the product is packaged in to a box and the Pallets are holding the boxes together with straps being looped around.

Luckily there is a mode that is very handy just for that!
It is a boxes mod:https://mods.factorio.com/mods/paradigmsort/boxes
It essentially has the exact same approach for packaging things like the barrels but with boxes... Now, my suggestion would be; to combine those two modes into one.
The items would be packaged into boxes first and later could be put on top of a pallet. At this point, they could act as another box for boxes... Or as a 2x2 chest for boxes. Or maybe your own implementation of "ULTIMATE EFFICIENCY PACKAGING!" or something like that )))))))

nice idea in the first place to have pallets and other similar means to make belts more interesting and increase throuphput for them. maybe the concept of pallets could be extended a bit, eg by first having cheap and easy to research wooden pallets (the base of them, smaller capacity like a quarter of a stack) and later with more research steel "cages" built on top of them for full stacks per pallet. (btw: i just saw those two variants when shopping: wooden base for few boxes with cans and metal cage for lots of bags of potatoes)

also a nice idea to use pallets on boxes, BUT having a pallet of 50 boxes of 50 ore each would result in 2500 items in a single item, or in case of a train 40 of those pallets (even when the pallets don't stack) for a total of 100k ore per wagon and throughput of blue belts also 100k per second (or 360M per hour:-) ... "hey, let's get some ore" ... a minute later: "ok, where shall i now deliver the entire ore field that i mined dry in half my large train?"

in case that someone wants to do crazy things like this, or starts mining on a very distant 100M+ ore field with a dozen bucket wheel excavators that each can fill a blue belt, it would be nice to keep the two mods compatible and avoid conflicting names etc so that people CAN use both, but please not as default in a single combined mod.