I think part of the problem with warlocks right now is there's just no incentive to only do a short rest when you can do a long rest instead and regain all your seplls and abilities for everyone. So the warlock gets all the drawbacks of having so few spell slots, but don't really gain any benefit from being able to get them back on a short rest.
Definitely big part of the issue.
I hope down the road in release they will offer at least 3 short rests for 1 long one to let short rest dependent classes their spotlight opportunity.
