I would think the main reason the pre release kit would see an increase in value is if the stamped cards go up in price significantly.
While that might not happen soon, the cards seem like there is room for growth long term
Actually their are only 8 Times as many Regular Kits as their are staff charizards. (Staff charizards only appeared in 1/4 case)
In addition a vast number of these kits would have been opened at events, thus decreasing the number of sealed kits in existence compared to the staff charizard card. (after the release I called around to over a dozen stores that hosted the prerelease events, all but 1 store used up all the kits at their events)- I called stores all over Canada and the United states trying to track some down.
If history is to set any presidency, sealed pokemon products tend to go up in value. The less of them in existence the greater likelihood it will go up. Right now their has been a decent supply of them on the market since the release, so we dont know exactly what will happen when the supply becomes inconsistent as more people either store them away in the personal collections/open the kits to get the prerelease holo cards.
Personally I think the kit will eventually command a higher price as the supply available on eBay eventually dwindles, in addition, I’m in the opinion people will continue opening them up, to grade the prerelease holo cards, further decreasing the population of these sealed kits.
Not sure how rapid growth will be, some of the Evo prerelease cards still seem pretty cheap! But I was honestly surprised that PSA 10 staff zard is still $4K+ card. I thought it being overpriced (imo) could negatively affect the other evo prerelease cards, but it still commands that amount, so I am pretty comfortable with the others going up.