It's speeding up a bit now fortunately.1. If the bottleneck is your physical machine, then all you can really do is install a big fuck off SSD with decent write performance. (this would make games load a lot faster, too)
2. Get a good internet connection
Are you downloading it from the store, if so, what's your download speed?
It's takes a good 1.25 hours to download a 30gb game on my 50mbit connection.
I would recommend purchasing games via DISC, installing from the store takes a while, and usually the price is a fair bit more than the stores.It's speeding up a bit now fortunately.