Ask HN: How should I handle this weird situation with angel investors?

Let's assume I get angel funding for a Travel Site. Neither I nor the Angels knew if the site would be successful or what kind of products we would launch in the future. Angels take 10% of the company, the site grows and eventually launches additional sites that target a similar audience - perhaps Luggage Buyers. Angels now own 10% of the Travel Site plus all the other sites that were created. This is all good so far.

Now let's assume I get angel funding for the same Travel Site, but this time, I have a complete strategy in place that outlines all the future sites we're going to launch once this becomes successful.

Is it better to let the Angels know what the plans are for the future sites, so that they are more eager to invest? Or should you keep it to yourself in case the Travel Site fails, in which case you can still go after those opportunities yourself without worrying about legal issues from the Angels?

Also, if you do let the Angels know about the future sites, is it possible to stipulate that they will not be automatically invested in those sites?