Add an Ensembl genes track
Since you have the UCSC and RefSeq genes already, why not add the Ensembl genes as well?
Also, I notice you're using hg19 as the assembly, but the GRC official name is GRCh37. How about labelling it as hg19/GRCh37 as UCSC does?
Nice work! It's fast, simple, and pretty!