Before you get too serious about plotting out your comic, you need to decide which audience you are shooting for. Your audience will determine a lot about your comic.
Consider that, when it comes to law enforcement, there are several different types of agencies: bureaus, sheriffs, highway patrol, police departments, and security guards. Each one has its limitations and jurisdictions; those define the law enforcement agency, and what it does.
A bureau is the most geographically unlimited agency. At the international level, national, and state levels, they can pursue lawbreakers within their jurisdictions, and can call on a lot of resources that the other agencies just can’t touch. However, it faces two major limitations: First, their investigations must be within their bailiwick (so that the Bureau of Alcohol, Tobacco, and Firearms, for example, can only deal with crimes that deal with alcohol, tobacco, and firearms; if the crime involves drugs, they can only notify that agency). Second, they need to worry about things that will affect a lot of people, not just a very local area; if the investigation shows that the crime is localized, they will usually turn it over to the local authorities.
Highway patrols are the second most ranging, but they are limited to traffic crimes; they do have some investigative patrolman, but they are limited to crimes involving vehicles and roads. They have a lot of power in those areas (especially given their isolation), but have limited jurisdiction.
Sheriffs have a lot of power locally, but must bow to the other agencies first. This isn’t to say that they are weak; just very focused on a specific locality. Although there is some competition with bureaus (as some investigations may be under different jurisdictions, due to the laws being broken and scope of the crime), the sheriff usually takes care of crimes that affect the county.
The police department takes care of the rest of the crimes. As such, they tend to deal the most with jurisdiction issues (being the low man on the totem pole, after all), and tend to deal with the most heinous crimes.
Oh, and let’s not forget security personnel; although limited to citizen arrest powers, they do help in some investigations, as well as catching some crooks. They have very limited powers, and extremely limited areas. And they automatically fold when it comes to jurisdiction issues, as they have none.
So, where does you comic fit into this? Most comics are like security guards; they are generally limited to jokes specific to a specific game or genre, and are most funny to your friends and family, but, well, just aren’t ready for general release. These are more in-jokes and other weirdness than anything else. Just post them, and let it go.
Good gaming comics and “artsy” strips (those trying to do something experimental or just more interested in the art) are like police departments in that they tend to be well-known is specific circles, and get a lot of word of mouth, but don’t really get fans. They may get the occasional reader, but have problems sustaining those numbers over a period of time. Some graduate to sheriff status, and actually get some fame, and tend to make a lot of “READ THIS!” lists, but are usually limited to a specific forum or group. Think Jhonen Vasquez strips; although interesting, they have a limited range of fans. A lot of comics at Drunk Duck and Comic Genesis fit these criteria. Most of the income associated with these strips (ad it’s not much!) comes from the donation button.
Highway patrol is where a lot of genre-strips and slice-of-life comics end up. Although they tend to have a specific focus, they tend to cover a lot of ground (this is where Sex Percussions fits in; it focuses on a specific group of people, but tends to make fun a lot genre conventions). Generally, fantasy comics make up the bulk, but there are a lot college strips and other fun stuff in this category. These strips are fun to read, and tend to attract a certain notoriety; tend to think Keenspot or Spider Forest type of comic strips. At this stage, you can add merchandise, and some of it may actually sell!
The majors are the bureaus. These are the strips that just don’t bother with the Top Ten lists (such as Buzzcomix); they have enough readers as is, and even show up in news stories about webcomics. They sell merchandise, get a lot of donations, and tend to have fans that follow the artists around. At worst, they have some notoriety (such as MegaTokyo) or stir up some controversy on their own (such as Penny Arcade or PvP).
At any rate, figure out where you belong, and plan your marketing accordingly…