Upon reflection, the original rule used a Dexterity check that did not require any special skill on the part of the caprine, so I'm reluctant to have the only Dex-based option be the Trained Only skill Tumble.Let's go for Perform (dance) or Tumble. Does my proposed notes = check result - DC work for you? I think the 3.X equivalent would be DC 10.
How about making it a DC 10 ability check OR a DC 15 skill check?
Dancing: The caprine dances dizzily for at least 10 minutes with one or more willing dance partners. At the end of this period, the caprine attempts either a DC 10 Dexterity check, a DC 15 Perform (dance) check or a DC 15 Tumble check. If they succeed, they accumulate resonance notes equal to one plus the amount by which their check result exceeded the DC up to a maximum equal to the number of partners the caprine is dancing with. For example, a caprine that rolled 14 on a DC 10 Dexterity check would earn 5 resonance notes from Dancing provided it has five or more dancing partners.
I've thought of another couple of points I wanted to raise.
The original resonance accumulation abilities were level-dependent, as follows:
Cavorting: No level requirement
Music (changed to Performing): caprines level 2 or higher
Drinking: caprines level 3 or higher
Dancing: caprines level 4 or higher
Reveling: caprines level 5 or higher
Consorting: caprines level 6 or higher
Should we stick to that? It would be a simple matter of adding to "Caprines of 4 or higher Hit Dice can perform this resonance method." I'm inclined to forget about it for the Music and Drinking abilities since those are within the limits of the 3 HD "Normal Monster" version of the original Caprine.
Also, I was thinking we should add the following general rule:
With the exception of the most basic method of Cavorting, all resonance methods require skill or ability checks and the participation of one or more partners. The Aid Another action cannot be used to enhance the checks made to strike resonance but any other bonus to skill or ability checks apply, including the use the caprine's empowerment ability. Two or more caprines may simultaneously strike resonance off each other – for example, a group of caprines in a "dance party" can each use the dancing method and include the other caprines as their dancing partners. Each caprine in such a group makes their resonance checks separately.