Great thread Brice...it's time I contribute my knowledge to arena newbies 101 
. A few suggestions/tips I'd like to make are below:
One item can make all the difference.
In some no move tourneys, similar sets will be run. Sometimes, two players can run the exact same setup, except for one item. That item is crucial...if you run armor/damage on it, and you're up against another armor set, that will be the item that wins you the round. But at the same time, that item can also be the item that keeps you from beating a defense set by a slight margin (an attack rune would've made the difference). A normal arena setup will always have multiple sets (except for a few of the epic heavy low levels), and most likely will have a few filler items that are not part of sets. Choosing the right filler items is very important.
The more sets, the merrier.
This rule does not always apply, but in many situations, you want to have at least 3 full sets equipped, if not four. There should be no surprise to this; it's clear that sets (with set bonuses) give far more stats than individual items, except for epics. These sets should always contribute to either attack/armor/damage, or attack/defense/damage. In no move arenas, no particular stat should be significantly higher. You want a good blend of all three, if possible.
Having dots to spend helps, but is not essential.
Unlike most other arena players, I actually run on a very low budget. I currently have 136 FSP, which is decent, but not a significant amount. Many of my items are unforged, and a couple are even uncrafted. I only have three combat sets, eight combat move sets, and 88 BP space (only 30 are filled with arena items). Most of the items I use are guild tagged (I buy them, but no BP space and I'd like others to share the items, so I tag them). While that does slow me down a little, and make my moves a little more predictable, it is still quite possible to do well in the arena without a thousand dots. I've titan hunted some of the epics I needed, and I get the rest of my gear off hunting (20 FSP per hunt), and selling items from the arena tokens I have. That, by itself, is enough for me to buy the items I need, albeit often unforged.
If any of you have any questions, feel free to ask me! I'm all for promoting new players into the arena 
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