Point of this post is to emphasize how limited the available content in the beta is.
First things first. Beta has only 1 city, 1 traditional quest line and 2 ish levequests or so per discipline.
There are only 4 areas to explore (massive, but still only 4). 1 area is similar in variety as 1 area of XI. Imagine having windy, Sarutabaruta region, and the mountains.
Jobs are limited to the very basic jobs. Similar to how XI is limited to 6 fighting classes at start.
Content in the beta is not set in stone. It has changed in every version, from the battle system to the way XP is gained and stored. Example: You used to be able to use physical levels to manually increase your HP and MP. This has since changed. They also used to have Elemental and Physical stats all deduct from the same points. Game was 100x laggier, crashed with a mere 500 people per server.
There are very few bugs.
As many of the testers have discovered, there is the beta version of the game, and then there is the game. Because of how limited the beta version is, it is a completely separate version than the final product. They are adding in features as they need them tested, not as they are adding them to the game. This also causes some bugs that may already be fixed to creep up again, as the beta version is probably an old version of the game.
That all being said, here are ways to be helpful:
Don't post about bugs or mechanics and your opinions of them on this forums. There is a forums specifically for feed back. The feedback threads are relatively well kept, and they get read. Posting about bugs or issues with game mechanics here will only lead to people getting the wrong impression of the game.
Remember that SE is treating this beta version as a beta version and not a free preview. This means that the content is SEVERELY limited in quantity and quality. Again, going back to a scale most of you can grasp well, it would be the same as playing XI with the only quest available in the entire game being the mission for the town you are allowed to use. Then imagine that the farthest you can go in missions is 2-3. That would be the extent of the quests in XIV at the moment. No one in the beta is getting any information that would give them any real advantage over a player starting on August 22nd.
What SE wants most out of it's testers would be their reactions. That alone is what they want, and what you should be posting in the beta forums. It is invaluable having 100k reactions sorted into threads on different subjects a full month before release.
At any rate, good luck, have fun, make babies.