FC: Joey
BC: Lopez
I, of course, have a lot less viewing experience than many on this board in regard to the greats throughout history that I saw live. However, after watching a lot of video of many of the greats (Bolivar, Joey, Atain, etc.), I think that the big guns in the modern era are better. And, since Lopez is the dominant big man of this time, he is the best, with Irastorza close behind.
However, I give the best front-court ever title to Joey in the front because of his innovation of the remate. I don't know how much of a game-changer his play actually was, but my impression is that front-courters could survive with a strong catch and throw game. Now, without some considerable offensive skill, a front-courter cannot even crack the early games at the big 2. I should note, however, that I think Goiko would beat Joey in a head-to-head with clone back-courters. So, maybe that makes him the best.
The single best player ever is something that can never be declared. There is such a distinction between what a front and back-courter does and what skills define the best at the two positions, there is no way to compare. For argument's sake, let's say that the two best at each position currently are:
FC - 1. Goiko 2. Solozabal
BC - 1. Lopez 2. Irastorza
In comparing Goiko to Lopez, there's no way to do it. On a relative basis, is Lopez more better than Irastorza than Goiko is better than Solo? Doesn't the defensive nature of the back-court position naturally bring the talent gap between the top two a lot closer than in the front? No way to tell, except maybe singles jai-alai. But that's a different type of game all together and back-courters are at a disadvantage with the larger baskets.
