Do not have Straight Life, but have other albums from his later(75-82) output.
For me, it's his ballads during this time that make me a pretty big fan. I liked him right off the bat, but I could see him being an acquired taste or having his detractors. I usually do not recommend him to jazz newbies. He is so intense and emotional that I almost have to 'get prepaired' before listening. Was he in a league of his own in this regard? He seems very unique, and along with Hodges, a no brainer when I want to hear a ballad.
I like him because he could play so very beautifully when he wanted to and then so very painfully, for lack of a better term.
As a person, well.....his autobio says it all. I was not shocked or surprised by his life. Very surprised that he would write about it. It was a fairly interesting read, but nothing special or unusual if you knew or were around drug addicts. As with most artists, I really do not care about their personal lives. It's none of my business and can get in the way of me enjoying their music.
If you do not have much 'later' Pepper in your collection I'd say try:
Ballads By Four with Art's 'Over The Rainbow', Today, and one of the Nights At The Village Vanguard albums, and take it from there.