One of the great (and very important) features of GSA is to be able to limit the number of submission or verifications that are made per day. The problem is that right now it gets a little messy when you have multiple URLs you are submitting... and even more messy when it's second tier.
The problem is that you typically want to submit to each URL a certain number of times per day... but when setting up a second tier, the number of URLs changes. So if you set it at 500 per day, at first when there is just 1 first tier that meets the criteria, that 1 gets 500 submissions, which is too many. Later, when there are 100 first tiers that meet the criteria, they each only get 5, which is too few.
It would be great if there was just 1 extra checkbox that said "per URL". This way if you select 100 per day, and "Per URL" is checked, then it would limit it to 100 per URL.