Hi,

I don't know if I missed an option, but I suggest an aesthetics to create an arrow according to the strand feature.
geom_gene_arrow(aes(direction = strand))

The effect of this aesthetics must be the direction of the arrow, this way it may support non-overlapping genes in the same y axis.

I don't know how to represent when it has overlap.

Another suggestion, to better fit the name of the molecule, is an option where the text might be placed below to arrow representation.

'>>gen1>>##>>>>>>gen2>>>>>>###<<<<<<<gen3<<<<<<<##>>>>>gen4>>>>>>'
'Melecule name or text'