Something that's not been addressed here, but probably should be, is whether you intend to compete in powerlifting at all.
If you intend to compete, then obviously it would behoove you to get comfortable with either a mixed grip or a hook grip.
If you are not competing, but lifting for self-satisfaction and fun, then just use straps. Yeah, yeah, you won't develop your grip as much. So? On the flip side, if your grip is the only thing holding you back from lifting a load that your back and legs might otherwise be able to handle, you're arguably depriving yourself of further strength development. For some reason this is often glossed over.
Finally, I guess the last point is that there is a middle ground available, right? What would be wrong with using straps for high-rep sets in training (if the pain is the limiting factor), but occasionally doing singles with the hook grip to keep that locked in for competitions if you're doing something where straps are not permitted?