I was thinking about running this duo

Beta Ray Bill 159
Enchantress 141

Would this do OK? Has anybody tried it?

Haven't tried it, but I get the feeling you'll get beaten more often than not. Here's why:

-only two figures in a 3 action round, you'll get out actioned and likely outmaneuvered.
-No mastermind fodder for enchantress. When you play a figure over 100 points that can use Mastermind, having some fodder gets very important to protect the investment.
-A big hit to either figure hurts you a lot as each one is half your team.

You do have a few things going for you though:
-TK means you'll get first strike a lot of the time.
-Mind Control with ten range and two targets is great against certain teams.
-Mystics can slowly ping an opponent down.

Bottom line: You can compete with some teams, but the more balanced and competitive teams will eat you for lunch.

-Immortal_Raven

Enchantress really isn't worth her points imo. I would switch her out for Maleketh ( saves you 50 points) and add in valkrye for 38. Malekith has tk as well so he can help get the first hit, and his mc going through characters make him really good, also, with the addition of valkyrie, you get a support that doesn't ruin your theme team, which is very useful.

If you have it, add in the Indigo Lantern. (I think thats the one that makes support better)