The super ideal cut stones don't generally go past 40.9 for pavilion angles. Lesser pavilion angles may show hearts and arrows but won't be super ideal cut.
It is almost the same as asking: What dish goes best with béarnaise-sauce?
You will surely get people recommending some kind of steak, while nobody knows whose béarnaise-sauce or if you even are searching in the direction of steak.
The reality, a cutter can combine a great 34.2 with other proportions, and produce a magnificent diamond. Or he can produce another 34.2 average with similar proportions and produce what one can call at best a decent or reasonable stone.
For a rule of thumb pure physics, the lower the crown, you'd want steeper complimentary pavilion angle in order to maximize the goal of dispersion fan growing as it passes through more diamond material, especially related to the principle applying to the perceived fire. The basic 2D rule still applies to diamond brightness without having to factor in the intricacies of the compound virtual mirror facets alighting together to create higher dispersion by 3D superideal cuts.
Having said that, my opinion is that you'd be best to stay in the range of 40.8-41 for best compliment for both brightness and fire in the most simplistic sense.