Establishing personality from shape AND color preferences
The question made me think instantly of the Kiki/Bouba effect. This effect is seen when people are to ascribe the name Kiki to point shapes and and Bouba to rounded shapes (Fig. 1); the overwhelming majority calls the star Kiki and the blob Bouba. One hypothesis is that Bouba is associated with the round shape because a more rounded shape is made by our mouths when Bouba is said. The mouth is more angular shaped when we say "Kiki." Additionally, "K" is a harder-sounding letter than "B." Those who use the modern Latin alphabet may also be visually swayed: the written letters "K" and "B" are sharp and rounded, respectively (Scientific American, November 2012).

Follow-up studies on this effect have revealed that people 


Associate between femaleness and round shapes, and maleness and sharp shapes. 
associate adjectives previously judged to be either descriptive of a figuratively 'round' or a 'sharp' personality with names containing either round-or sharp-sounding phonemes, respectively. 


The authors conclude that sound symbolic associations extend to existing lexical stimuli, and that form and meaning are non-arbitrarily mapped (Pexman &amp; Sidhu, 2014).

Reference
- Pexman &amp; Sidhu, Canadian J Exp Psych (2014); 68(4): 253-4


Fig. 1. Kiki and Bouba - which is which? source: Wikipedia