About the first issue: that is similar to how it work now, if i understood it correctly.
Ping batch is always unique - so you can aggregate 10 times and ping only once after that and each blog will be pinged only once.
I'll have to recheck that. At one point I believe I saw more blogs listed as updated but not pinged than I had created which would imply duped records in the batch table, but I will admit I may have looked at it wrong.
About second issue.. it can be done and will be as soon as possible.
If you will have your own plugin before our update, will be cool with us

I'm trying to work something up now, but the only way I know to do it is through a seperate ping software that I own.