Yeah I thought that too (hard to see) on some, but it may just be getting used to them from what we already have. We could go for 24x24 in size if you prefer, but I was thinking 16x16 might allow for more icons without infringing on too much real estate.
Of our current icons, I definitely prefer the 'single thumbs up' for LIKE, the 'teddy bear' for HUG, 'face palm', 'beer', '???' (which could be Really??? in a pinch).
I don't know how they would look sizewise/artwise with a new set, but maybe we can merge them.
No rush, we'll keep tweaking.