Earlier this week I wrote about some of the hows of limiting options for Players, which could be summarized as: be fair, let them know in advance, and try not to hamper their creativity.
Today's blog is about why you can and possibly should limit player options.
There are two ways to define something: explain what it is and explain what it is not. You classify what shape something is by where it ends, and the absence of something is an important clarifying feature. Doughnuts are defined because they have a whole in the middle. I spell it "doughnut" instead of "donut" because I'm Canadian, and our self-proclaimed defining feature is that we're not Americans.
One way to define a campaign setting is by what races are and are not present. Removing a common race from the equation creates a role and background vacuum that can be filled by other races. If you remove elves (like 3rd party games often did back in the TSR days and MMOs still use as a hook) suddenly you need a new wilderness race, a new race that’s archetypal for rangers, and another source for half-elves. This might leave room for the wilden, who suddenly have a much stronger role and place in the world. Instead of being a superfluous tacked-on race with no history, wilden become the defenders of the natural world and a race of druids and rangers.
This works best when the excluded race is a big-name race that will be missed. No one would notice if the kenku vanished. Dragonlance did this to some extent, with their world defined by its lack of orcs as the infantry of evil armies. They also added a new aspect to elves by removing drow as a race in the world.
Eliminating races helps other races shine!
Other times, changing the world results in a racial role that has no place. In a megalopolis setting that is one giant urban environment (such as a campaign taking place entirely in a city like Sharn, Waterdeep, Greyhawk, or Ptolus) there are no real forests so wilderness-centric races have no place. It's possible to have a fish-out-of-water race or character that lives in the region but has lost their way of life or is a foreigner from a far land, but more than one is overkill and makes the other redundant. The DM might pick one or two nature or 'savage' race (wilden, shifter, elf, and possibly goliath or half-orc) and remove the others. The reverse is also true; in a savage, primal campaign civilized races like humans, eladrin, deva and possibly tieflings might have a lesser role.
More races in the game give players and DMs options, more choices of what to include but also what not to include.
It does impact players if a beloved race doesn't exist, but hopefully they can be encouraged to use the replacement race in its stead. This works if they're picking the race for fluff or background reasons. If it's a mechanical selection then the mechanics can just be re-skinned as a race that does exist.
With 4e being a continually published and living game line, there are continually new options being added to the game. This can negatively impact campaign worlds written prior to the book's release.
I began re-writing my campaign world prior to 4e, but designed it around the new information and design tenants, finishing it shortly after the edition's release. I began a campaign quickly, around the release of Martial Power. With each new book's release I edited my wiki and campaign document to include the new options. Some new additions, such as deva and shifters, effortlessly found a role in my campaign and worked well with existing themes. Other races, such as goliaths, had to be forced-in and did not mesh as well as I would prefer. I haven't even tried with shardminds and wilden, and even the well-known githzerai might be awkward.
Some new options just do not match the theme of a campaign world, or the races fill a role already occupied by one or more races. Even if the new race better fills the niche, it's hard to replace a race already seen. The DM is forced into the unwinnable conflict between facilitating player choices & fostering player creativity, and maintaining a consistent narrative & a coherent world.
The fear of power creep also makes newer books unwelcome at many tables. Three editions of increasing power levels with new releases mean newer PC books are a worry. The reliance on spells 'n' powers for class abilities does mean the original classes won't be entirely overshadowed by later releases, but it does mean monsters and encounters might become trivial (or be radically increased in danger, like the Monster Manual 3 beasties).
Sourcebooks & Magazines
Related to the power creep in successive books, many DMs have banned "splatbooks" such as the Complete Fighter's Handbook or Complete Warrior or Martial Power. Campaigns or home games might be limited to only the Core three books or a series of must-have books. It would be easy to limit a 4e game to only the PHBs.
In the days of 3e, even the Living/RPGA games didn't have a blanket approval for all later publications. Living Greyhawk had a lengthy list of what was allowed and what was banned and the Eberron campaign required characters to "unlock" options every level or so.
My current 3e home game has limited access to secondary books, with DM approval required for feats and prestige classes. It seems to work but would be a little trickier with 4e where you'd need to possibly approve new content for every player every couple gaming sessions.
The design of 4e has made banning books a little trickier: a single build requires fifteen powers and there is usually only a couple builds for each class in each relevant book. There are a limited number of options for each class without using supplemental products. There is also the insistence "everything is Core" and that everything undergoes the same rigorous quality control and amount of development as the core books.
So why limit options?
4e is a fragile game, because of its intent to be completely balanced. Because everything is designed to be exactly the same power level, any deviation stands-out. While all products get edited, not every product is thoroughly play tested, and the size and frequency of Updates seems to indicate kinks are increasingly worked-out of powers and classes after release. With more mechanical content released for 4e than 3e, there are more potentially game-breaking interactions, so it makes sense to limit possible interactions and content that might not have been play tested by the community.
I have been tempted to limit new books until the first post-release Update. This doesn't work for Dragon as there are disproportionately fewer magazine powers featured in the Update documents.
Therefore, limiting options can lead to a more reliable play experience. Players do not have to worry about their characters being impacted or re-written by Updates and DMs do not have to worry about regularly fine-tuning encounters to reflect fluctuating PC power levels. And PCs don't have to worry as much about a single player intentionally (or unintentionally) dominating the game.
That's a few reasons to consider limiting options or having "everything but".