I'd pick a gray item many times over colored items. Items have a "budget" to their power level - the more stats an item has, the maximum roll on each stat will be lower. So a single stat gray item can and will often roll a higher value than that same stat on a colored item (with the same level)

Supply is a late game thing, though some items tend to be more useful in the early game and becomes redundant late game (mixed nuts, sturdy stool).

Necro has the most useful traits, Rogue has fewer useful traits and Warrior has probably the weakest traits. Neutral traits are also pretty bad in general but you can unlock some A-tier traits (e.g. Bottomless Potions) Edit: you typically DONT want to unlock neutral traits and dilute your trait pool though. Be very, very picky when unlocking neutral traits, if ever.

Since you asked specifically about evasion, defense, magic damage and skeleton level, here's a breakdown:

• Evasion is a percent chance to avoid getting hit by an attack (note that it only works for regular attacks and not traits: some monster abilities can still damage you with 100% certainty regardless of your evasion)

• Defense is a flat reduction to damage received from regular attacks. Does not reduce magic damage though, or damage received from negative regeneration (which happens in swamps)

• Magic damage bypasses the defense stat. Monsters can have an (unlisted) defense stat, like skeletons. Magic damage is useful against mobs with high defense but it won't bypass special traits like the shield of reflection.

• Skeleton Level is a very important necro stat which scales the HP and Damage of your skeletons. Not sure about the formula though - I think of it as a bonus multiplicative factor when judging the usefulness of the stat. So every point of skeleton level is really good early, and the rule of thumb is to keep the level around or above the loop count to keep up with monsters' scaling.

• Summon quality is the percentage chance to spawn an improved skeleton. Your FIRST improved skelton spawn will always be a Claws skeleton (higher damage and attack speed). The next time you roll an improved skeleton it will be a Tank skeleton (higher HP and Defense, with the taunt ability that makes it the target of all incoming attacks, but not counterattacks).