The biggest conundrum of the current size rules is 4 tiny creatures occupying the same square trying to attack 4 other tiny creatures occupying an adjacent square…they can't (maybe with reach weapons).
The small size category never really fit in with the sizing scheme in 3.X. Going up from medium, creatures take up more squares and have greater reach. Going down from small, creatures take up fractions of a square and have zero reach. But small and medium creatures each take up one square and have a five-foot reach. It doesn't make sense.
The first time the ceiling in a dungeon is 5' high instead of 10' high you notice the difference between small and medium characters and it makes sense. Granted this is an aspect of dungeon design often ignored flat out or ignored for "playability" reasons. Have folks build dungeons scaled to the actual builders and different sized PCs really shine.
and i do hope they stick with one dmage stat and simply have small, medium and large weapons. Small weapons in one hand for small folks and two hands for medium weapons with one stat for damage works fine .
