Honestly, the idea of implementing Discord-style reactions on Tumblr isn’t a completely terrible one.
Tumblr likes are functionally meaningless save as a mechanism for popular blogs to keep score anyway, so letting folks effectively colour-code their likes for individual posts by choosing a symbol to associate with them wouldn’t do any particular violence to the site’s functioning – it’d just get subsumed into the post’s overall note count.
However, I suspect that suddenly having dozens of icon to choose from when liking a post would be an intimidating adjustment for the site’s established userbase; it might be best to start gradually, with a smaller set of options – perhaps just three or four.
And you know, since we already have hearts