I have been playing around with doing deadlifts barefoot with both myself and my clients at the recommendation of Eric Cressey and top coaches. The idea behind this is to eliminate the unnatural heel lift typical of most athletic shoes, which mess with one's natural ankle mobility over time (an immobile ankle joint can adversely affect movement patterns at the knee & hip joints)
Before I started pulling deads barefoot (and with a trap bar), my low back was always the limiting factor on my deadlift, particularly the right side. After needing some chiro work on my R hip, knee, ankle this summer due a rugby misadventure, I have concluded that the root of my deadlift woes was/is probably my right ankle. It is stiffer and much less mobile than the left for some reason and probably always has been. Ever since I have been pulling barefoot (and going shoeless more often) my back has given me almost 0 trouble so there is definitely something to this idea. However, I have found that rolling a lax ball on my feet (10x) and doing ankle mobilizations (10x) really helps me get down deeper in my set up for deadlifts. If I don't do this, I don't feel as powerful at the bottom and my lifts aren't smooth past the knees.
Recommendation #1 - Pull deadlifts barefoot
Recommendation #2 - Roll your feet and mobilize the ankles beforehand to make it more effective. I have attached an instruction video by one of the top guys in our industry, Eric Cressey, on how to do this.