The ultimate goal for this in our opinion is such that of the “active set” of governance delegates, we should easily be able to reach quorum on votes that aren’t contentious. Even with dozens of messages being sent out to voters often times a day or two before the time ends (fyi to everyone we’ve sent these to, sorry for spam and bumps 
), we barely get to quorum on a majority of the votes.
In our eyes, this should at least be 50% more than quorum. So it ends up being that we’d like to see at least 60m+ votes active on each 40m quorum needed vote. Again, this would mean adding in an extra 15-20m of delegation on top of the 10m already being sponsored, which we also think would be a bit much in one go. Somewhere a little less such as 10m or so makes sense, and dividing it between some up to 2.5m and up to 1.0m delegates that @Tane propsoed earlier this week also makes sense.
Bottom line, over the last year, we have had quite a few qualified and active delegates enter governance, and we think these individuals should all 100% have enough delegation to at least sponsor a vote if they want to.