The best thing to do IMO is what other streaming sites I use do - not the best best thing to do, which would be to find another revenue model, but using the ad-based revenue model - and that is:
1. Have ads, but only ads with no audio. Video is fine, but no audio, or by default the audio is off.
2. Ads are relatively small, and above, to the sides of and below the video, not on top of it.
3. Ads are able to be hidden quickly and easily, should they actually cause problems for a user.
4. Videos are disabled on the site when ad-block is used.
Youtube, offering the superior generic video streaming service at the moment, could get away with something like this. It'd probably lose some people, but at the same time there'd be a lot who wouldn't really be impacted IMO. The key is to keep the ads non intrusive. Rather than locking content behind them, blasting them full volume, and generally impeding your customers use of your service with them, if they are kept there, noticeable, but not interrupting the service, most people won't bother closing them. The option is there for those who do want to. Because videos won't play with adblock running, people will also disable adblock to be able to watch the videos, and won't mind doing so as much because the ads aren't intrusive. Sure, maybe you won't earn as much money per ad, but you'll have a lot more ads being watched. Quantity over quality.
Of course, being a major company, youtube would still get flak for it. Some would refuse to use the service because they're actively acknowledging and further implementing ads, even though the method is favourable to the current one. But you'll keep your revenue, not annoy the customers you do keep, and eventually the others will get over it and move back. If you communicate that you're changing the ad scheme for user comfort, people might even give it a chance and not straight up leave.
Something like this though that actively antagonises your customers? Yeah, Google had better hope that none of its streaming competitors take advantage of this. If they were to make a big move at this point, and offer incentives to streamers to move to their service, whilst promising not to discriminate against customers using ad-block - they'd stand to gain a potentially significant portion of market share. Not enough to overtake Youtube, but enough that Youtube would have to think twice about its practices or else they may eventually do so.