Here and here are Talysman's posts where he hates "niche protection." It's a question of who-can-do-what in a role-playing game. I agree that the rules should be based on a view of what characters can do that has its own integrity, not manufactured to create some outcome at the player level.
And yet - especially when it comes to magic - there's such a variety of plausible ways of doing things that we can't help but choose among systems. In that case, why not choose wisely? As I argued a while ago, a good game will strike a balance between making a given skill set useful while not making it strictly necessary.
So you get a slightly less effective fighter with one less hit point on average, worse attack and limited weapons, BUT:
Average HP restored from those two Cure Light Wounds: 9
Average HP of a first level fighter: 5.5
That's right, a character who not only fights in their own right, not only turns undead and can do miscellaneous other things with spells, but provides a force multiplier in the course of play (assuming damage is not taken in huge lots) equal to almost two fighters.
The decision in OD&D and B/X to not give clerics ANY spells until 2nd level in hindsight seems reasonable, although Labyrinth Lord climbs down from this with 1 spell at 1st level and so on. Even without bonus spells this is still a pretty nice force multiplier, that lags behind the fighter's hit dice at middle levels but perks up with the ability to cure serious wounds and raise dead at higher. The choice, still, is not ideal; between a game where clerics have to prove their gumption by spending their first level as a sucky fighter who can turn undead, and a game where clerics are seen as mandatory to the point where people will play them even though they don't really want to.
I've seen first-hand in my gaming group the dismay with which players face the prospect of adventuring without a cleric (my 52 pages version has a healing power that likewise is a pretty big force multiplier). The obvious fix is to do what I did with wizards to stop the "sleep/magic missile" fixation; allow only one example of each spell to be cast a day. Because my system lets spells become available at every character level, I could even give a very minor healing spell at cleric character level 1 and the Cure Light Wounds equivalent only at cleric character level 2.
This might be the last major change to the 52 Pages, but I think it achieves the goal of letting clerics feel useful at Level 1, but not indispensable at higher levels. Hell, I might even give them their at-will turning back.
1 hour ago