It all depends what your trying to do with highscore.domains.
Is it purely a fun project / experiment? Or are you interested in making money out of it. If its the later then I can see how "deals" (and thus affiliate revenue) might be worth while adding.
Why not do it on the letsmakeadeal domain and link to it from highscores?
You are right, let me try it at as a separate project in letsmakeadeal and see how it goes...
The reason for not doing that so far is that, don't want to start another project and goes stale. I guess we never know without trying!
I like it. I wonder if the relevancy of the deals is important? Just about every domain registry has coupon codes / deals. You could start by populating it with those?