Everything. There are so many variables that go into what makes
a cesta just right (tener bien) for an individual pelotari. It
is truly more an art than science. As a start:
length (62/63 cm for FC 64/65 cm BC)
hook -fast (less hook ) or slow
fundo (pocket) depth and style
width between arros (ball sticks better with
narrow but easier to tick the frame)
thickness of the ribs (costillas)
width of the arros (strength vs flexibility)
overall weight (strength vs light weight)
tip (punta) style (flat vs curved)
glove softness
Ondress Egurbide was well know to make the most beutiful, stong
and overall highest quality - he had a select cleientele including
Boli, Elorza, Ondarres, Cachin Uribar etc.
Xavier Egurbide also made a wonderful cesta - it was slightly
stonger (heavier) and less flexible than the Ondress variety
There was a guy in Tampa (Xavier Alanis) who made a great catchers
basket. soft fondo - ball stuck like glue. Also a wonderful soft
glove (guante)
Too many to mention - everyone has their own unique favorite.
What always amazed me the most is the guys like Chimela who played
amazing jai-alai with narrow, deep, beat up, taped up, over-used
pieces of crap.