These are some things that I learned from the critique with the visiting artist about the comic assignment that we did where we had to have made up a word and have a hero and animal character.
A good idea is to start right off with action, especially if it is a shorter comic and you want to grab the attention of the viewer. This is not always the case however, when there is a lot of action it can become jumbled and you do not want to lose the interest of those who are reading and looking at the comic. Starting slowly and then building up to action can be just as effective as massive explosions in the first panel. With that said, it is important to remember that you do not want to ruin the pace with a lack of clarity. Sometimes it can help you if you maybe change the layouts and thicknesses of outlines around the panels and leave some empty space as well.
Xeroxing work is a wonderful way to experiment with color and layouts. You can cut things up and place them anywhere and then make a xerox of the layout you just made. It is really all about finding what works the best for you, what you are most comfortable with. I am not saying "stay in the comfort zone" though. Perhaps try to reach outside of a comfortable boundary by experimenting with different colors and mediums and techniques that you research or come up with by yourself.
When thinking comics it is an important note to keep in mind the balancing of picture and word balloons. It is the combination of style and story and what you are really trying to say. This can incorporate even something as simple as where you use line and where you do not use line in a panels or page layout. A limited palette could help balance forground and background or even distinguish the nature of the characters used, good, evil, neutral etc...
One interesting thought I received from the visiting artist is that not everything in your own comic has to be absolutely inked. Sometimes a pencil can do what inking just cannot accomplish, sometimes inking might ruin the effect that the pencil has given you. Another thing to keep in mind is that too much information can bog the viewer down and make something boring to read or overwhelming to look at. Another way of dealing with this is to not feel confined to having everything stuck in a box or panel at the same time that you need not feel redundant in showing the same backgrounds in every panel.
Things to watch out for would be:
No contrast from one panel to the next
making it look too dense, no varying line weights
Making everything with words be conversational and ranting
having words take over the panels, unless that is your intent
etc... etc... etc...
There are as many diverse comics as there are diverse people and I am not saying at all the some are better then others because that all depends of the side or view that you have on them. They may have been done in similar styles but they are each different in their own ways. Everyone is a critic and it is all opinion.