Undoing hair damage caused by bad care habits?

Okay, so I've got a decent sized afro but have never actually looked into how to take care of it until very recently. Having done so now, I've realized that I've done almost everything wrong besides using bad shampoos (mostly because I neglected washing it a lot).

Anyways, I'm thinking that my hairline's weird shape is probably caused or at least exacerbated by the fact that I would always run a pick through it really hard to get the tangles out. It's always tangled a lot and the front sides are usually the worst part in terms of length, so I tended to pick that part out even harder than other places. A lot of people say that damages the roots and can make the hairline start moving back early, so I just want to ask, is this reversible? I'm trying to take much better care of it but I just started so I don't expect to see anything yet. Is there a chance it'll grow back? It's not at a horrible point or anything (and it might not even be caused by this) but I'd still like to see it improve if I can. If I take better care from now on, could it improve or is the damage already done?