Thanks Gustavo for the enhancement suggestions!
We have just released v4.3, which includes various enhancements around Dashboard, so you should give it a shot!
1, 2 - We'll consider for adding to the future enhancement list.
3 - For now, this is automatically adjusted based on how many charts are in each row.
4, 5 - This is on our list, probably in 4.4 or 4.5.
6 - Is this for formatting the number values in Table and Pivot?