Heretic doesn't suffer from this problem. Has the same # of weapons as Doom.
Oh yes, let's take a look at the Heretic arsenal.
Reskinned fist from Doom
Reskinned chainsaw from Doom
Reskinned pistol from Doom
Shotgun replaced with the crossbow, which is a nice weapon
Reskinned minigun from Doom
Reskinned rocket launcher from Doom
Can't even remember what the sixth weapon was
BFG replacement fires a large, slow-moving bouncing projectile that (IIRC) can split into smaller projectiles
If I missed any weapons, it's because I can't remember them. See below.
The problem with Heretic's arsenal is that it's
dull. Dull equals forgettable. Quantity doesn't automatically trump quality.
Now compare that to the Hexen weapons. Each class has a smaller arsenal, but each part of it is well thought out, giving each character a different playstyle as a result.
The Fighter has the best starting weapon and prefers to get up close and personal. The Mage has the weakest starting weapon but it's ranged and has infinite ammo, so he has to keep his enemies at a distance. The poor Cleric is left bashing at his enemies with a spiked club until they die of boredom. But as the classes get more weapons, their power 'status' changes. The Fighter, while still powerful, will be simply dwarved by the damage output of the Mage (Bloodstorm to the face = Death) while the Cleric has the 'I Win'-weapon of the game with the Wraithverge.
Also, the Flechettes act differently depending on which class is using them. This adds the fifth weapon to each class. Then there's stuff like the Chickenator, the pocket Minotaur and the force push to flesh out the arsenal even further.
All this before we get to the point that Hexen's combat is designed to be less 'point-and-click' and more tactical than in other FPS games. I wouldn't say that it's a full-blown success in that regard, but they did a decent job of it.