As both a mod and a player, the things I like to see for writing examples/game history, are the following:
Recent examples of the player's writing; a couple different threads are good, and bonus points if they involve different charactes, archetypes, genre, scene, et cetera. I.E: An action thread vs a casual conversation scene. Personally, I prefer a mix of example threads; for one idea, it could be the first several replies of a single thread, so each player/character has three or so posts each. Just providing the first post or a middle post, and without your partner's response- it can throw people off.
You can always provide a little blurb before the thread example, explaining the general idea of what's going on, the location, etc, especially if the example is from the middle of a scene or towards the end. =D
A general idea of the types of games that the player's been in, is also awesome; not every single RP that the person's joined throughout their entire RP-life, though. Just listing the names of past games is good, especially for cases where the games are no longer up-and-running, or have been deleted. Links to recent games, retired or active- is also very helpful.
As for characters, you can catalogue them appropriately: genre, fandom, PB or not PB, animated/rendered, cross-overs/panfandom and so forth. You can use lists, link to journals and asylums, include mini portraits (or not), use simple table codes, and so forth. It largely depends on how many RPs you join, if you regularly change your active/retired/whathaveyou characters and memberships.
Of course, using codes will take some time to reorder things as needed, but using such things shouldn't scare players and staff away. It's just a way of presenting your RP history, nothing more.