Change by how much? We won't know until we start measuring and make that process and its results standards.
That is EXACTLY why standardization will help! Get 5 or 6 factors standardized and remove this subjective, fussy feeling nonsense. On top of that, it will easy to replicate "the feel" with custom bat makers when there are standards for bats.
Sorry but no simply no.
Have you ever been in a workshop??
Willow is too varible. Ask the batamkers themself they if there honest will tell you. Most people pay for stickers and straight lines.
You can not standardize williow.
even machine made bats have varients no matter how much you think.
Most of the things you want to standardise are peronal opinion.
Mate i too at times when i was younger would love standardization.
To put your point in to question anybody go to a cricket shop and pick a bat up. Remember the first bat you picked up then go around the shop take over 5 minutes then come back to that bat. I almost guarentee you it will feel different. Your idea of a number here may work but people even have difference of thoughts on pick up(what picks up well for player a may be different to player b). Then add gloves or no gloves as you know bats feel different with gloves on.
Inital Ping test then retest after a year i guarentee you this there will be no pattern of results.
In my theory is 90 per cent of all bats are equal and there no difference in rebound quality after a period of use.
The difference is the person holdding the bat ability feel and pick up and shape which is all personal.
We love a good yarn but in truth a bats a bat all mostly end up the same to most users.
Us on here though love to talk about mythical things, grains wide narrow who pressed and the mythical Pro bats.
I will admit when i did a little bit for a company i did do the marketing nine yards but in truth over the 10 years on here and 100 of bats most have been the same no matter what the grade-i just liked the pick up and shape at the time.