We can add more reactions - to ludicrous amounts, if we so desire (we don't). The one click to open the list makes sense to me - besides it's just how the addon works. As for making it smaller .. Hmmm.... we can. But there was also a thought about changing the icons. I'd rather do all that together ... assuming we get around to doing it. (/just lazy)
I can live with clicking on a icon to get to the list, I'd prefer the immediacy of them all just being there. Though I do find it a bit misleading that you have to click on a button that says 'Like' first to select the reaction which could be quite different.
I just stumbled on this which looked kind of neat:
I've actually seen that addon and considered installing it. Unfortunately, it's a Xenforo v1 addon and we are on Xenforo V2. That author didn't update the addon for v2 and among all the options, I ended up installing what we now have.