First Thomas' comment again
I'm not 100% sure you're being fair the the battlerager.
1) It comes from the Complete Book of Dwarves. Its not actually just Forgotten Realms at all. Though the Book of Dwarves battlerager doesn't use spiked armor specifically, the book does give an option for knee and elbow spikes, so you're maybe right about the ridiculousness of specializing in the armor. It must have been after 2nd edition that the class became associated with spiked armor, but a google image search surely turned up a good deal of spiked armor.
2) Battlerager armor says you get to use spiked armor as a weapon. This isn't clear to me if you can only use the bonus action attack or if you can use it as your main attack too. Its slightly better if you can use spiked armor as your main weapon as it prevents you from being disarmed, which just requires an interpretation rather than house ruling something totally new. Though if you could use it to attack with your regular attack action, they should have called that out clearly and you'd think they would have if that was the intention.
3) You get to make that Battlerager Armor bonus action attack while you're either wielding a two-handed weapon or a shield. So you could easily have an AC of 18 as the battleraging barbarian getting two attacks on most rounds. Still kinda sucks that its only while raging, but you get it when the damage bonus kicks in, and its more opportunities for hits. Also works with the Brutal Critical feature. So have those handaxes for while you're not raging, but make use of a versatile weapon or bite your shield when you start to rage. The bonus action attack is still better than normal two-weapon fighting too, as you're doing d4+str damage on a hit at 3rd level instead of normal two weapon fighting's plain d4 or d6.
4) Grapple's pittance of damage still isn't great, but you can also still make that bonus action attack if you're raging while grappling. And the point of grappling is probably to stop people from moving, not to deal massive damage.
5) Dash as a bonus action (Battlerager Charge) is a way of saying you don't need ranged weapons as much. Sure it competes with your silly spiked knees and elbows, so you'll only used it to catch up with your enemies if you really need to. But you can do that, no spending your actual action to dash and doing nothing during a combat round.
6) The Battlerager Charge also works well with the grapple, as you can pull someone half your speed while you've grappled them, and if you dash you're pulling someone around at full speed.
7) That said, you're totally right about it basically being rage-only features. It might be nice if the battlerager got advantage to intimidate people (or at least other dwarves), could use the spiked armor outside of combat, or whatnot. As it stands, I'm not sure why the normal berserker path isn't appropriate for what the 2nd edition Book of Dwarves lists as the battlerager. I don't think the battlerager is as hopeless as you're saying it is, though if it shines it probably does so after 5th level, so its a bit moot for our upcoming dwarf game. Its still probably better at 5th level than the berserker though, even if either of those are less satisfying than a fighter.