Many of the original base keywords are "evergreen" and still used commonly in Magic design as of 2019, such as Flying, First Strike, and Trample
Colorless spells on the other hand can be played in any deck, so if there were too many great colorless instants, those cards would start being played in pretty much every deck
12 tile trays included for modular mounting
Of course, it has to die to do that, which means your opponents have to choose if its worth sacrificing their creatures, being slowly pinged to death, or just biting the bullet and hoping theyre not your target
The fact that it costs eight mana also hardly seems like a concern, given how easily green can pull ahead of other colors with land ramp and mana dorks
However, once you seal the card with finish at the end there is no going back.