idbeholdME: The only thing I'm conflicted on are some RPG games, especially those that don't have a respec option. Take Baldur's Gate or Icewind Dale for example. There are a ton of weapon specilizations, but you have no idea how supported that weapon type is. An extreme example:
You might end up going flails and only find out after 30 hours that 80% of the weapons are swords and axes and there are barely any flails at all.
This particular example, to me, is something I consider to be a design flaw. What happens here is essentially the following:
* You have to make an irreversible choice, without any knowledge of what's in the game, at level 1.
* At character creation, there isn't any obvious difference between the choices. In other words, there's no basis for picking one choice over the other, so it feels arbitrary, and is a choice the player has to make without any information.
* And then, of course, the choices might very well not be balanced, like in your example.
In fact, there's one other instance of game design where the player has to make an uninformed choice, and is punished for making the wrong one, and that's pick-a-path in things like Mario Maker troll levels. Basically:
* You are presented with multiple ways to go. In the Mario Maker games, this would typically be multiple doors and/or pipes, but it doesn't have to be.
* There isn't anything that would point you toward one particular choice as opposed to the others.
* But if you take the wrong one, you die.
I note that, even in the troll Mario Maker community, pick-a-path is considered bad level design. Hence, for similar reasons, I'd argue that weapon proficiencies and specializations, at least in a Baldur's Gate-like context, is also bad game design.
As for ways this could have been done better:
* Make it reasonable to train a new weapon type later in the game. This is best done by not tying weapon proficiency to level ups. One example of this is Final Fantasy 2 (which doesn't use XP leveling in the first place); if you find that your weapon type isn't that useful, you can switch to another weapon type and eventually become good at it. (FF2 has other issues, including a hidden variable that should not have been hidden plus some "noob traps" that are particularly nasty, but the weapon proficiency system isn't one of them.)
* Distinguish the weapons in a clear and obvious way. Lords of Xulima does this, with the different weapon types having different secondary effects. (Again, there's other issues, namely the fact that one particular ability score is basically mandatory, but at least the game gets this aspect correct.)
* Just not use a weapon proficiency system at all. After all, the Gold Box games (and other SSI games), Dragon Quest 1-7, Final Fantasy games (at least until each character would get only one weapon type, and excluding FF2), Ultima, and Wizardry 1-5 work just fine without any weapon proficiency system. (Wizardry 6-8 are more like FF2 with weapon proficiency, but without the main issues that game had, and with a more conventional approach (including XP based leveling) in most other areas.