However, how do you actually list your coins? Is it just completely random, or have I missed something?
The coins are listed by their symbols alphabetically, with one exception that BTC is always shown first because it's the most popular - I know it's not ideal.
I agree with you that the coins should be sorted either by market cap or volume. I'll add a note to fix that in the near future (as more coins will be added).
Otherwise, add more coins, and exchanges. There's less than 100 coins right now, definitely not enough. But having too many exchanges on one page doesn't really work either, might have to come up with a solution. I don't really like the fact that there are so many "N/A"s on the page also.
Yes, good point - I'm adding more coins soon and exchanges will follow as well. I'm a bit swarmed with another project right now - but will get to it soon.
About the "N/A"'s - I've been planing a small re-design of the table to make those "N/A"'s a bit less annoying

I like the fact that you can see the prices from individual exchanges in real time updating. That is the real plus for me for using this site. Intuitive, and straightforward unlike some other price tracking sites. So it's definitely a well done on that.
I appreciate your constructive feedback!
Thanks