You heard me. FUCK YOUR ROGUE. Your rogue class is likely the worst part of your game, and you should be ashamed.
With whatever that was out of my system, let’s talk about what I mean by the above tirade. In many OSR games, the rogue class is both wholly unnecessary, and likely a hinderance to new, or less creative players.
In general, rogues can be typified in one of two ways: the skill monkey, or the one who does the thieving. The first is generally acceptable, but the second produces a strange disconnect in the minds of many players, especially those coming to RPGs for the first time, or those who aren’t the most creative. Few OSR games have a skill system and thus are not likely to identify by the first moniker. LotFP & SWN stand out here, but we’ll get to them in a second. This usually means the second moniker, which has some obvious problems, as well as some smaller, more nuanced problems.
The Problem with the Thief Table
The thief table is wired, some of these are 1-in-6, some are d%, and others, in some systems are 2d6. This problem extends beyond the thief to other checks (break bars? listen at doors?) but is most apparent because the thief has several of them. Why we put up with this at all is beyond me, but it’s tradition, so we’re stuck with it, aren’t we?
It’s actually becoming more common in OSR circles to modify these systems to other mechanics. I’ve seen the thief table converted to flat d20, 2d6, X-in-Y, and other various methods. These attempts are a good first step to solving the problem, but fail to resolve the larger issue.
The Real Problem with the Thief Table
The thief table is a lie. By defining the chance of specific tasks, as done by a thief, there is an implied rule that does not actually exists. By way of comparison, let’s look at Turn Undead another whipping boy of mine. The cleric can turn undead, and because it’s not mentioned anywhere else, it can be assumed that non-clerics cannot. The thief can pick pockets, and because it’s not mentioned anywhere else, non-thieves… Wait.
Now many are already rushing to my email to tell me "Just because there isn’t a rule, doesn’t mean non-thieves can’t pick pockets" and "Rulings not rules!" I accept your poor rebuttals, and counter by suggesting that these arguments don’t hold water to people who are not accustom to ignoring the rulebook. The OSR (and to a lesser extent, rules-light play) is a strange beast among games. Very few games subscribe to this "Rulings over Rules" mentality, and thus those new to the game fail to remember it in the moment, and no, another reading of PA is not going to get them to remember it when it matters. Instead, it’s up to the rules to imply that anyone is allowed to try anything unless they are specifically NOT allowed to try something.
In Mike Merals' Unearthed Arcana on Feats he calls out the feats shouldn’t "… serve as a barrier that prevents a character without the feat to [perform the given action]". Similarly, class features should be written with the same advice in mind. If a class feature provides a specific functionality, it must be assumed that this functionality is impossible to members of other classes, OR that the feature provides bonuses to the attempt.
Experts & Specialists
Before we get on to the big question, I want to call out two classes that understand the problem I’m describing and handle it appropriately. Both LotFP and SWN do have skill systems (of a sort) and thus, provide a class that is focused on being good at those skills. This is totally acceptable, if a bit fiddly at times, and should not factor into this discussion.
Why Even Have a Thief
In short, don’t. The thief was an addition from Greyhawk in the original LBB, and in my opinion, is an unnecessary add.
In longer form, ask yourself why you want to add the class. More than likely it’s one of 2 reasons, either having a dex-focused class for those who want dex-to-damage and the like, or because your fighter is too boring, a topic I’ll talk more on later. For those looking for a dex based class, I suggest tweaking your thief into an assassin of sorts. Give the character easy access to poisons, and provide bonuses to sneaking and hiding.