I don't think the adds should enrichen the users of the steem blockchain only. It should also support the witnesses and the ones who do have to pay for the infrastructure. Otherwise, the user could get more steem and the problems for the ones who do pay the infrastructure do stay the same.
Also here we could use Scorum again as example. Where 40% of the income of the adds will go to the reward pool and the others will go the ones who do have to pay the infrastructure and the witnesses!

So adds fine by my but the rewards should be distributed fairly and depending on the costs they have. Maybe for the users the showing/viewing for adds is the price they have to pay to make use of this free blockchain!

This sounds like a good idea to me!

I don't have any problems with a small doze of advertising. Small is here the keyword. Let's take Scorum as example! They do have adds placed on their pages. And they are placed smart. They do catch attention but they don't distract!

Indeed, and so a notifications (6) showing unread ads, ready when you are ready would suit?

Also if they are going to allow adds, is this then only on the steemit frontend or will they force this also on @busy, @esteem or @steeve

They could all do it separately, without anyone else's permission. Just like if someone developed a browser extension - they might want a cut, which seems reasonable.

Thanks for the comments, I've got a splitting headache and I'm going to reply to the rest in the morning.